Method, device and equipment for smooth control of engine torque of hybrid system

Abstract

The present application relates to a hybrid system engine torque smoothing control method, device and equipment, the method comprises: determining the torque smoothing critical value of the current moment based on the engine speed of the current moment, the engine actual torque of the current moment, the remaining power of the power battery and the minimum value of the battery pack monomer temperature; In the case of determining that the engine demand torque of the current moment is greater than the torque smoothing critical value, the first smoothing demand torque of the engine of the current moment is determined based on the smoothed torque increasing step, and the compensation torque of the motor is determined based on the first smoothing demand torque; In the case of determining that the engine demand torque of the current moment is less than or equal to the torque smoothing critical value, the second smoothing demand torque of the engine of the current moment is determined based on the original torque increasing step of the engine of the current moment, and the compensation torque of the motor is determined based on the second smoothing demand torque. Avoid the engine to appear smoke limit, avoid the engine torque response to be limited, more fuel-efficient.

Description

Technical Field

[0001] This invention relates to the field of engines, and in particular to a method, apparatus, and device for smooth control of engine torque in a hybrid power system. Background Technology

[0002] Hybrid commercial vehicles based on the P2 architecture experience smoke limits under certain conditions in hybrid mode, such as after a gear shift when the engine is driven at full throttle, which restricts engine torque response and increases fuel consumption. Therefore, effectively avoiding engine smoke limits, limiting engine torque response, and achieving better fuel economy are pressing issues that need to be addressed. Summary of the Invention

[0003] This invention provides a method, apparatus, and device for smooth control of engine torque in a hybrid power system, which solves the problem in the prior art where the engine reaches a smoke limit after shifting gears at full throttle, resulting in limited engine torque response and increased fuel consumption. This invention effectively avoids the engine reaching a smoke limit, prevents limited engine torque response, and improves fuel efficiency.

[0004] A method for smoothing engine torque in a hybrid power system includes: determining a torque smoothing threshold based on the current engine speed, the current actual engine torque, the current remaining charge of the power battery, and the minimum temperature of a single battery cell; the torque smoothing threshold is positively correlated with the current remaining charge of the power battery and the minimum temperature of a single battery cell, and the torque smoothing threshold is the maximum smoothed engine torque to avoid the current engine smoke limit; if the current engine torque demand is greater than the torque smoothing threshold, a first smoothed torque demand for the engine is determined based on a smoothed torque increment step size, and a compensation torque for the electric motor is determined based on the first smoothed torque demand; wherein the smoothed torque increment step size is negatively correlated with both the current remaining charge of the power battery and the minimum temperature of a single battery cell; or, if the current engine torque demand is less than or equal to the torque smoothing threshold, a second smoothed torque demand for the engine is determined based on the current engine torque increment step size, and a compensation torque for the electric motor is determined based on the second smoothed torque demand.

[0005] In one embodiment, determining the torque smoothing threshold based on the current engine speed, the current actual engine torque, the current remaining charge of the power battery, and the minimum temperature of a single battery cell includes: determining an initial smoothed engine torque value based on the current engine speed, the current actual engine torque, and a preset first mapping relationship; wherein the first mapping relationship reflects the maximum smoothed engine torque value after the engine reaches its smoke limit or highest fuel consumption under different engine speeds and actual engine torques; the initial smoothed engine torque value at the current moment is the maximum smoothed engine torque value after the engine reaches its smoke limit or highest fuel consumption at the current moment; determining a scaling factor based on the current remaining charge of the power battery, the minimum temperature of a single battery cell, and a preset second mapping relationship; wherein the second mapping relationship reflects the scaling factor corresponding to different current remaining charge of the power battery and different minimum temperatures of a single battery cell, and the scaling factor is positively correlated with the current remaining charge of the power battery and the minimum temperature of a single battery cell; and determining the torque smoothing threshold based on the initial smoothed engine torque value and the scaling factor at the current moment.

[0006] In one embodiment, determining the first smoothed torque demand of the engine at the current moment based on the smoothed torque increase step size, and determining the compensation torque of the electric motor based on the first smoothed torque demand, includes: adding the smoothed torque increase step size and the engine demand torque at the current moment to obtain the first smoothed torque demand of the engine at the current moment; determining the compensation torque of the electric motor at the current moment based on the first unsmoothed torque demand of the engine at the current moment, the first smoothed torque demand, and the compensation torque of the electric motor at the previous moment; wherein, the first unsmoothed torque demand is the sum of the engine demand torque at the current moment and the original torque increase step size of the engine at the current moment.

[0007] In one embodiment, before determining the first smoothed torque demand of the engine at the current moment based on the smoothed torque increase step size, the method further includes: determining the smoothed torque increase step size based on the current remaining charge of the power battery, the minimum temperature of the battery pack cells, and a preset third mapping relationship; wherein, the third mapping relationship is the relationship between the smoothed torque increase step size and the current remaining charge of the power battery and the minimum temperature of the battery pack cells.

[0008] In one embodiment, determining the torque smoothing critical value based on the initial value of the engine smoothing torque at the current moment and the scaling factor at the current moment includes: determining the torque smoothing critical value based on the product of the initial value of the engine smoothing torque at the current moment and the scaling factor at the current moment.

[0009] In one embodiment, determining the second smoothed torque demand of the engine at the current moment based on the original torque increment step size of the engine at the current moment, and determining the compensation torque of the electric motor based on the second smoothed torque demand, includes: adding the original torque increment step size of the engine at the current moment and the engine demand torque at the current moment to obtain the second smoothed torque demand of the engine at the current moment; determining the compensation torque of the electric motor at the current moment based on the second unsmoothed torque demand of the engine at the current moment, the second smoothed torque demand, and the compensation torque of the electric motor at the previous moment; wherein, the second unsmoothed torque demand is the sum of the engine demand torque at the current moment and the original torque increment step size of the engine at the current moment.

[0010] In one embodiment, determining the compensation torque of the motor at the current moment based on the second unsmoothed demand torque of the engine and the second smoothed demand torque at the current moment, and the compensation torque of the motor at the previous moment, includes: calculating the difference between the second unsmoothed demand torque of the engine and the second smoothed demand torque at the current moment; and adding the difference to the compensation torque of the motor at the previous moment to obtain the compensation torque of the motor at the current moment.

[0011] The present invention also provides a smoothing control device for engine torque in a hybrid power system, comprising: a first determining module, configured to determine a torque smoothing threshold value at a current moment based on the current engine speed, the current actual engine torque, the current remaining charge of the power battery, and the minimum temperature of a single battery cell; the torque smoothing threshold value is positively correlated with the current remaining charge of the power battery and the minimum temperature of a single battery cell, and the torque smoothing threshold value is the maximum smoothed engine torque value to avoid the current engine smoke limit; a second determining module, configured to determine a first smoothed demand torque of the engine at a current moment based on a smoothed torque increase step size when the current engine demand torque is determined to be greater than the torque smoothing threshold value, and to determine a compensation torque of the electric motor based on the first smoothed demand torque; wherein the smoothed torque increase step size is negatively correlated with the current remaining charge of the power battery and the minimum temperature of a single battery cell; or, a third determining module, configured to determine a second smoothed demand torque of the engine at a current moment based on the original torque increase step size when the current engine demand torque is determined to be less than or equal to the torque smoothing threshold value, and to determine a compensation torque of the electric motor based on the second smoothed demand torque.

[0012] A computer device includes a memory and a processor, the memory storing computer-readable instructions that, when executed by the processor, cause the processor to perform the steps of the smooth control method for engine torque in a hybrid power system described above.

[0013] A storage medium storing computer-readable instructions, which, when executed by one or more processors, cause the one or more processors to perform the steps of the smooth control method for engine torque in a hybrid power system described above.

[0014] The aforementioned method, device, and equipment for smoothing engine torque control in a hybrid system avoids smoke opacity limits by smoothly controlling engine torque. Specifically, by jointly determining the engine torque smoothing critical value that is unlikely to cause smoke opacity limits at the current moment, based on the engine's actual operating state (e.g., current engine speed and current actual engine torque) and the state of the power battery (e.g., current remaining battery charge and minimum cell temperature of the battery pack), a smoothing critical value for engine torque is determined. Based on this critical value, it is then determined whether to use a smoothed torque increment step size, the required smoothing torque for the engine, and the compensation torque for the electric motor, thereby achieving smooth control of engine torque and avoiding smoke opacity limits. Furthermore, the smoothed torque increment step size is determined based on the actual state of the power battery, allowing for a more comprehensive assessment of the electric motor's torque-sharing capability and determining a more accurate smoothed engine torque increment step size, which is more conducive to smooth engine torque control. Secondly, since the electric motor assists the engine in torque compensation when the motor battery is sufficiently charged, engine changes during driving are slower, reducing transient engine fluctuations and saving fuel. Moreover, the torque supplementation by the electric motor improves the overall vehicle's dynamic response. Attached Figure Description

[0015] Figure 1 This is one of the flowcharts illustrating a method for smooth control of engine torque in a hybrid power system provided in one embodiment;

[0016] Figure 2 This is a second schematic flowchart of a method for smooth control of engine torque in a hybrid power system provided in one embodiment;

[0017] Figure 3 This is a third flowchart illustrating a method for smooth control of engine torque in a hybrid power system, as provided in one embodiment.

[0018] Figure 4 This is a fourth flowchart illustrating a method for smooth control of engine torque in a hybrid power system, as provided in one embodiment.

[0019] Figure 5 This is a schematic diagram of a framework for a smooth control method of engine torque in a hybrid power system provided in one embodiment;

[0020] Figure 6This is a schematic diagram of the structure of a smooth control device for engine torque in a hybrid power system provided in one embodiment. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0022] It should be noted that, unless otherwise defined, the technical or scientific terms used in this invention should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0023] To facilitate understanding, the technical terms used in this application will be explained first.

[0024] Smoke opacity: A physical quantity measuring the degree of darkness of the gas and solid mixture produced by engine combustion.

[0025] For ease of understanding, the inventive concept involved in this application will be explained.

[0026] Hybrid commercial vehicles based on the P2 architecture experience certain special operating conditions in hybrid mode. For example, after a gear shift, the engine may experience smoke limits when driven at full throttle, leading to restricted engine torque response and increased fuel consumption. Therefore, reducing transient changes in engine torque during normal driving and using the electric motor for torque compensation can achieve fuel savings. When smoothing engine torque is required, the step size of the torque increase needs to be calibrated, and the accuracy of the calibration significantly impacts fuel efficiency.

[0027] The present invention provides a method for smoothing engine torque control in a hybrid power system. By smoothing the engine torque, it avoids smoke opacity limits. Specifically, it determines a critical value for smoothing engine torque that is unlikely to cause smoke opacity limits based on the engine's actual operating state (e.g., current engine speed and current actual engine torque) and the state of the power battery (e.g., current remaining battery charge and minimum cell temperature). Based on this critical value, it determines whether to use a smoothed torque increment step, the required torque for engine smoothing, and the compensation torque from the electric motor, thus achieving smooth engine torque control and avoiding smoke opacity limits. Furthermore, the smoothed torque increment step is determined based on the actual state of the power battery, allowing for a more comprehensive assessment of the electric motor's torque-sharing capability and resulting in a more accurate smoothed torque increment step, which is more conducive to smooth engine torque control. Secondly, when the motor battery is sufficiently charged, the electric motor assists the engine in torque compensation, making engine changes during driving slower, reducing transient engine fluctuations and saving fuel. Moreover, the torque supplementation by the electric motor improves the overall vehicle's dynamic response.

[0028] The following description, in conjunction with the accompanying drawings, describes a method, apparatus, and device for smooth control of engine torque in a hybrid power system according to the present invention.

[0029] like Figure 1 As shown, in one embodiment, a smooth control method for the torque of a hybrid power system engine is proposed. This smooth control method can be executed by a smooth control device for the torque of the hybrid power system engine, which can be an electronic control unit (ECU). The ECU can be an ECU on a vehicle. Specifically, as... Figure 1 As shown, the smooth control method for engine torque in a hybrid power system provided by the present invention may include the following steps:

[0030] Step 110: Determine the torque smoothing threshold at the current moment based on the current engine speed, the current actual engine torque, the current remaining charge of the power battery, and the minimum temperature of the battery cell.

[0031] The torque smoothing threshold is positively correlated with the current remaining charge (SOC) of the power battery and the minimum temperature of the battery cell. The torque smoothing threshold is the maximum torque of the engine after smoothing to avoid the current smoke limit of the engine.

[0032] In this invention, the minimum temperature of a single cell in the battery pack can be understood as the actual temperature of the cell with the lowest temperature among all cells in the battery pack under normal operating conditions.

[0033] It is understandable that the ability of the electric motor to share the torque of the engine can be evaluated based on the SOC of the power battery and the minimum temperature of the battery pack cells. Therefore, the SOC of the power battery and the minimum temperature of the battery pack cells can be combined with the current operating state of the engine to determine the torque smoothing threshold at the current moment, thereby determining whether the engine torque smoothing is needed at the current moment.

[0034] In conjunction with the preceding text, to avoid issues related to engine smoke opacity limits, a torque smoothing threshold can be determined based on the engine's actual operating state (e.g., current engine speed and current actual engine torque) and the state of the power battery (e.g., power battery SOC and minimum cell temperature). This threshold can be used in stages to determine whether to employ a smoothed torque increment step size to determine the engine's smoothing torque requirement. Specifically, when the power battery has a significant remaining charge and the minimum cell temperature is high, the smoothed torque requirement is determined using the smoothed torque increment step size. Furthermore, based on the engine's smoothed torque requirement, the torque requiring motor compensation can be further determined. For details on different processing methods based on the smoothed torque increment step size, refer to steps 120 or 130.

[0035] Step 120: If the engine's required torque at the current moment is greater than the torque smoothing threshold, determine the engine's first smoothed required torque at the current moment based on the smoothed torque increase step size, and determine the electric motor's compensation torque based on the first smoothed required torque.

[0036] The smoothed torque increase step size can be understood as the smoothed torque increase step size of the engine at the current moment, determined based on the state of the power battery. The smoothed torque increase step size is negatively correlated with the power battery SOC and the minimum temperature of the battery pack cells.

[0037] It's understandable that the ability of the electric motor to share torque with the engine can be assessed based on the battery's State of Charge (SOC) and the minimum temperature of each individual battery cell. A higher SOC means the electric motor can share more torque with the engine, while the engine can share less torque. Therefore, with a higher SOC, the smoothed torque increase step size is negatively correlated with the battery's SOC. Furthermore, under normal battery conditions, a higher minimum temperature of each individual battery cell means the electric motor can share more torque with the engine, while the engine can share less torque. Therefore, the smoothed torque increase step size is also negatively correlated with the minimum temperature of each individual battery cell.

[0038] Step 130: If the engine's required torque at the current moment is less than or equal to the torque smoothing threshold, determine the engine's second smoothing required torque at the current moment based on the engine's original torque increment step size at the current moment, and determine the electric motor's compensation torque based on the second smoothing required torque.

[0039] The present invention provides a method for smoothing engine torque control in a hybrid power system. By smoothing the engine torque, it avoids smoke opacity limits. Specifically, it determines a critical value for smoothing engine torque that is unlikely to cause smoke opacity limits based on the engine's actual operating state (e.g., current engine speed and current actual engine torque) and the state of the power battery (e.g., power battery SOC and minimum cell temperature). Based on this critical value, it determines whether to use a smoothed torque increment step, the required torque for engine smoothing, and the compensation torque of the electric motor, thereby achieving smooth engine torque control and avoiding smoke opacity limits. Furthermore, the smoothed torque increment step is determined based on the actual state of the power battery, allowing for a more comprehensive assessment of the electric motor's torque-sharing capability and resulting in a more accurate smoothed torque increment step, which is more conducive to smooth engine torque control. Secondly, when the motor battery is sufficiently charged, the electric motor assists the engine in torque compensation, making engine changes during driving slower, reducing transient engine fluctuations and saving fuel. Moreover, the torque supplementation by the electric motor improves the overall vehicle dynamic response.

[0040] In one embodiment, such as Figure 2 As shown, step 110 above includes:

[0041] Step 210: Determine the initial value of the smoothed torque of the engine at the current moment based on the engine speed at the current moment, the actual engine torque at the current moment, and the preset first mapping relationship.

[0042] The first mapping relationship is used to reflect the maximum smoothed engine torque after the engine reaches the smoke limit or the highest fuel consumption under different engine speeds and actual engine torque conditions; the initial smoothed engine torque value at the current moment is the maximum smoothed engine torque after the engine reaches the smoke limit or the highest fuel consumption at the current moment.

[0043] It is understandable that the first mapping relationship can be determined by fitting data to a mapping table obtained from experiments on a test bench. Specifically, a mapping table can be obtained by determining the smoothed maximum engine torque value that corresponds to the highest smoke limit or fuel consumption under different engine speeds and actual engine torque conditions. Then, the first mapping relationship can be obtained by fitting data to the mapping table.

[0044] Step 220: Determine the scaling factor at the current moment based on the power battery SOC, the minimum temperature of a single battery cell, and the preset second mapping relationship.

[0045] The second mapping relationship is used to reflect the scaling factor under different power battery SOC and different minimum cell temperatures of the battery pack. The scaling factor is positively correlated with the power battery SOC and the minimum cell temperature of the battery pack.

[0046] Step 230: Determine the torque smoothing critical value based on the initial value of the engine smoothing torque at the current moment and the scaling factor at the current moment.

[0047] Specifically, step 230 includes: determining the torque smoothing critical value based on the product of the initial value of the engine smoothing torque at the current moment and the scaling factor at the current moment.

[0048] It is understood that the above only provides one possible way to implement the torque smoothing critical value. In practice, other methods can also be used to determine the torque smoothing critical value at the current moment. For example, add corresponding weights before the initial value of the engine smoothing torque and the scaling factor, and calculate the product of the weighted initial value of the smoothed torque and the scaling factor to determine the torque smoothing critical value.

[0049] In one embodiment, such as Figure 3 As shown, step 120 above includes:

[0050] Step 310: Add the smoothed torque increase step size to the engine's current torque demand to obtain the engine's first smoothed torque demand at the current moment.

[0051] The above process can be expressed by the formula: N'0 = T0 + S'0, where N'0 represents the first smoothed torque demand of the engine at the current moment, T0 represents the engine torque demand at the current moment, and S'0 represents the torque increase step size after smoothing.

[0052] Step 320: Determine the compensation torque of the electric motor at the current moment based on the first unsmoothed demand torque of the engine, the first smoothed demand torque, and the compensation torque of the electric motor at the previous moment.

[0053] Among them, the first unsmoothed demand torque is the sum of the engine demand torque at the current moment and the original torque increment step of the engine at the current moment.

[0054] Specifically, the difference between the engine's first unsmoothed required torque and the first smoothed required torque at the current moment can be calculated first. Then, this difference is added to the motor's compensation torque at the previous moment to obtain the motor's compensation torque at the current moment. This process can be expressed by the formula: N0b = N0 - N'0 + N -1 b=(T0+S0)-(T0+S'0)+N -1 b, where N -1 b represents the compensation torque of the electric motor at the previous moment, N0b represents the compensation torque of the electric motor at the current moment, N0 represents the first unsmoothed torque demand of the engine at the current moment, T0 represents the engine's torque demand at the current moment, and S0 represents the original torque increment step size of the engine at the current moment. It can be understood that the methods for determining the compensation torque of the electric motor at the previous moment and the compensation torque of the electric motor at the current moment are similar.

[0055] It is understandable that, since the compensation torque supplied to the motor is the total torque required by the motor, the compensation torque of the motor at historical moments needs to be accumulated.

[0056] In one embodiment, prior to step 310 above, the method further includes:

[0057] Based on the SOC of the power battery, the minimum temperature of the battery pack cells, and the preset third mapping relationship, the smoothed torque increase step size is determined; where the third mapping relationship is the relationship between the smoothed torque increase step size and the SOC of the power battery and the minimum temperature of the battery pack cells.

[0058] In one embodiment, such as Figure 4 As shown, step 130 above includes:

[0059] Step 410: Add the original torque increment step of the engine at the current moment to the engine's required torque at the current moment to obtain the second smoothed required torque of the engine at the current moment.

[0060] Step 420: Determine the compensation torque of the electric motor at the current moment based on the second unsmoothed demand torque and the second smoothed demand torque of the engine at the current moment, as well as the compensation torque of the electric motor at the previous moment.

[0061] Among them, the second unsmoothed demand torque is the sum of the engine demand torque at the current moment and the original torque increment step of the engine at the current moment.

[0062] Specifically, the difference between the engine's second unsmoothed demand torque and the second smoothed demand torque at the current moment can be calculated; the difference can be added to the motor's compensation torque at the previous moment to obtain the motor's compensation torque at the current moment.

[0063] Figure 5 This is a schematic diagram of a framework for a smooth control method for engine torque in a hybrid power system provided by the present invention. Figure 5 As shown: The current engine speed and actual engine torque are input into a preset first mapping relationship to obtain the initial smoothed engine torque value C. Simultaneously, the power battery SOC and minimum battery cell temperature are input into a preset second mapping relationship to obtain the scaling factor f. The initial smoothed engine torque value C is multiplied by the scaling factor f to obtain the torque smoothing critical value T. Then, the torque smoothing critical value T is compared with the current unsmoothed engine torque demand to determine whether the smoothed torque increase step size S'0 or the original torque increase step size S0 is used as the current engine torque increase step size. After determining the current engine torque increase step size, combined with the current engine torque demand T0, the current smoothed engine torque demand is determined. Therefore, based on the current smoothed engine torque demand and the current unsmoothed engine torque demand, the current motor compensation torque can be determined.

[0064] The smooth control device for engine torque in a hybrid power system provided by the present invention will be described below. The smooth control device for engine torque in a hybrid power system described below corresponds to the smooth control method for engine torque in a hybrid power system described above.

[0065] Figure 6 A schematic block diagram of a smooth control device for engine torque in a hybrid power system provided by the present invention. Figure 6 As shown, the smooth control device for engine torque in a hybrid power system provided by the present invention includes:

[0066] The first determining module 610 is used to determine a torque smoothing threshold value at the current moment based on the current actual engine torque, the current remaining charge of the power battery, and the minimum temperature of a single battery cell. The torque smoothing threshold value is positively correlated with the current remaining charge of the power battery and the minimum temperature of a single battery cell, and the torque smoothing threshold value is the maximum smoothed engine torque value to avoid the current engine smoke limit. The second determining module 620 is used to determine a first smoothed demand torque of the engine at the current moment based on a smoothed torque increase step size when the current engine demand torque is determined to be greater than the torque smoothing threshold value, and to determine the compensation torque of the electric motor based on the first smoothed demand torque. The smoothed torque increase step size is negatively correlated with the current remaining charge of the power battery and the minimum temperature of a single battery cell. Alternatively, the third determining module 630 is used to determine a second smoothed demand torque of the engine at the current moment based on the original torque increase step size when the current engine demand torque is determined to be less than or equal to the torque smoothing threshold value, and to determine the compensation torque of the electric motor based on the second smoothed demand torque.

[0067] In one embodiment, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the following steps corresponding to a method for smoothing the torque of a hybrid power system engine: determining a torque smoothing threshold value at the current moment based on the current engine speed, the current actual engine torque, the current remaining charge of the power battery, and the minimum temperature of a single battery cell; the torque smoothing threshold value is positively correlated with the current remaining charge of the power battery and the minimum temperature of a single battery cell, and the torque smoothing threshold value is used to avoid the engine reaching a smoke limit at the current moment. The maximum engine torque after smoothing; if the engine's current torque demand is greater than the torque smoothing threshold, the first smoothed torque demand of the engine at the current moment is determined based on the smoothed torque increase step size, and the compensation torque of the electric motor is determined based on the first smoothed torque demand. The smoothed torque increase step size is negatively correlated with the current remaining charge of the power battery and the minimum temperature of a single battery cell. Alternatively, if the engine's current torque demand is less than or equal to the torque smoothing threshold, the second smoothed torque demand of the engine at the current moment is determined based on the original torque increase step size, and the compensation torque of the electric motor is determined based on the second smoothed torque demand.

[0068] On the other hand, the present invention also provides a computer program product, the computer program product comprising a computer program stored on a non-transitory computer-readable storage medium, the computer program comprising program instructions, wherein when the program instructions are executed by a computer, the computer is able to execute the smooth control method for engine torque in a hybrid power system provided by the present invention, wherein the smooth control method for engine torque in a hybrid power system comprises: determining a torque smoothing critical value at the current moment based on the engine speed at the current moment, the actual engine torque at the current moment, the current remaining charge of the power battery, and the minimum temperature of a single cell in the battery pack; the torque smoothing critical value is positively correlated with the current remaining charge of the power battery and the minimum temperature of a single cell in the battery pack, and the torque smoothing critical value is To avoid the engine reaching the smoke limit at the current moment, the maximum smoothed engine torque is determined. If the engine's required torque at the current moment is determined to be greater than the torque smoothing threshold, a first smoothed torque requirement for the engine at the current moment is determined based on the smoothed torque increase step size, and the motor's compensation torque is determined based on the first smoothed torque requirement. The smoothed torque increase step size is negatively correlated with the current remaining charge of the power battery and the minimum temperature of the battery pack's individual cells. Alternatively, if the engine's required torque at the current moment is determined to be less than or equal to the torque smoothing threshold, a second smoothed torque requirement for the engine at the current moment is determined based on the original torque increase step size, and the motor's compensation torque is determined based on the second smoothed torque requirement.

[0069] Furthermore, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon. When executed by a processor, this computer program implements the smooth control method for engine torque in a hybrid power system provided by the present invention. The smooth control method for engine torque in a hybrid power system includes: determining a torque smoothing threshold value at the current moment based on the current engine speed, the current actual engine torque, the current remaining charge of the power battery, and the minimum temperature of a single battery cell. The torque smoothing threshold value is positively correlated with the current remaining charge of the power battery and the minimum temperature of a single battery cell, and the torque smoothing threshold value is used to avoid the engine reaching a smoke limit at the current moment, thus smoothing the torque. The maximum value of the engine torque after smoothing; if the engine torque demand at the current moment is greater than the torque smoothing threshold, the first smoothed torque demand of the engine at the current moment is determined based on the smoothed torque increase step size, and the compensation torque of the electric motor is determined based on the first smoothed torque demand. The smoothed torque increase step size is negatively correlated with the current remaining charge of the power battery and the minimum temperature of the battery cell; or, if the engine torque demand at the current moment is less than or equal to the torque smoothing threshold, the second smoothed torque demand of the engine at the current moment is determined based on the original torque increase step size of the engine at the current moment, and the compensation torque of the electric motor is determined based on the second smoothed torque demand.

[0070] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0071] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for smooth control of engine torque in a hybrid power system, characterized in that, The method includes: Based on the current engine speed, the current actual engine torque, the current remaining charge of the power battery, and the minimum temperature of the battery pack cells, a torque smoothing threshold is determined for the current moment. The torque smoothing threshold is positively correlated with the current remaining charge of the power battery and the minimum temperature of the battery pack cells, and the torque smoothing threshold is the maximum engine torque after smoothing to avoid the current moment's engine smoke limit. If the engine's current torque demand is greater than the torque smoothing threshold, the first smoothed torque demand of the engine at the current moment is determined based on the smoothed torque increase step size, and the compensation torque of the electric motor is determined based on the first smoothed torque demand. The smoothed torque increase step size is negatively correlated with both the current remaining charge of the power battery and the minimum temperature of each individual cell in the battery pack. If the engine's required torque at the current moment is determined to be less than or equal to the torque smoothing threshold, the engine's second smoothing required torque at the current moment is determined based on the engine's original torque increment step size at the current moment, and the electric motor's compensation torque is determined based on the second smoothing required torque.

2. The smooth control method for engine torque in a hybrid power system as described in claim 1, characterized in that, The determination of the torque smoothing critical value at the current moment, based on the current engine speed, the current actual engine torque, the current remaining charge of the power battery, and the minimum temperature of each individual cell in the battery pack, includes: Based on the current engine speed, the current actual engine torque, and the preset first mapping relationship, the initial value of the smoothed engine torque at the current moment is determined; wherein, the first mapping relationship is used to reflect the maximum smoothed engine torque after the corresponding engine reaches the smoke limit or the highest fuel consumption under different engine speeds and actual engine torques; the initial value of the smoothed engine torque at the current moment is the maximum smoothed engine torque after the engine reaches the smoke limit or the highest fuel consumption at the current moment. Based on the current remaining power of the power battery, the minimum temperature of the battery pack individual cells, and a preset second mapping relationship, the scaling factor at the current moment is determined; wherein, the second mapping relationship is used to reflect the scaling factor corresponding to different current remaining power of the power battery and different minimum temperatures of the battery pack individual cells, and the scaling factor is positively correlated with the current remaining power of the power battery and the minimum temperature of the battery pack individual cells. The torque smoothing critical value is determined based on the initial value of the engine smoothing torque at the current moment and the scaling factor at the current moment.

3. The smooth control method for engine torque in a hybrid power system as described in claim 1, characterized in that, The process of determining the engine's first smoothed torque demand at the current moment based on the smoothed torque increase step size, and determining the electric motor's compensation torque based on the first smoothed torque demand, includes: The smoothed torque increase step size is added to the engine's current torque demand to obtain the engine's first smoothed torque demand at the current moment. Based on the engine's first unsmoothed demand torque, the first smoothed demand torque, and the electric motor's compensation torque at the previous moment, the electric motor's compensation torque at the current moment is determined; wherein, the first unsmoothed demand torque is the sum of the engine's demand torque at the current moment and the engine's original torque increment step size at the current moment.

4. The method for smooth control of engine torque in a hybrid power system as described in claim 1, characterized in that, Before determining the engine's first smoothed torque demand at the current moment based on the smoothed torque increase step size, the method further includes: Based on the current remaining charge of the power battery, the minimum temperature of the battery pack cells, and the preset third mapping relationship, the smoothed torque increase step size is determined; where the third mapping relationship is the relationship between the smoothed torque increase step size and the current remaining charge of the power battery and the minimum temperature of the battery pack cells.

5. The method for smooth control of engine torque in a hybrid power system as described in claim 2, characterized in that, The determination of the torque smoothing critical value based on the initial value of the engine smoothing torque at the current moment and the scaling factor at the current moment includes: The torque smoothing critical value is determined based on the product of the initial value of the engine smoothing torque at the current moment and the scaling factor at the current moment.

6. The method for smooth control of engine torque in a hybrid power system as described in claim 1, characterized in that, The process of determining the second smoothing torque demand of the engine at the current moment based on the original torque increment step size of the engine at the current moment, and determining the compensation torque of the electric motor based on the second smoothing torque demand, includes: The original torque increment step of the engine at the current moment and the engine's required torque at the current moment are added together to obtain the engine's second smoothed required torque at the current moment. Based on the engine's second unsmoothed demand torque and second smoothed demand torque at the current moment, and the electric motor's compensation torque at the previous moment, the electric motor's compensation torque at the current moment is determined; wherein, the second unsmoothed demand torque is the sum of the engine's demand torque at the current moment and the engine's original torque increment step size at the current moment.

7. The method for smooth control of engine torque in a hybrid power system as described in claim 6, characterized in that, The determination of the motor's compensation torque at the current moment, based on the engine's second unsmoothed demand torque and the second smoothed demand torque at the current moment, and the motor's compensation torque at the previous moment, includes: The difference between the second unsmoothed demand torque and the second smoothed demand torque of the engine at the current moment is calculated; the difference is added to the compensation torque of the electric motor at the previous moment to obtain the compensation torque of the electric motor at the current moment.

8. A smooth control device for engine torque in a hybrid power system, characterized in that, include: The first determining module is used to determine the torque smoothing critical value at the current moment based on the current engine speed, the current actual engine torque, the current remaining charge of the power battery, and the minimum temperature of the battery pack cells. The torque smoothing critical value is positively correlated with the current remaining charge of the power battery and the minimum temperature of the battery pack cells, and the torque smoothing critical value is the maximum engine torque after smoothing to avoid the current moment's engine smoke limit. The second determining module is used to determine the first smoothed torque demand of the engine at the current moment, based on the smoothed torque increase step size, when the engine's current torque demand is greater than the torque smoothing threshold, and to determine the compensation torque of the electric motor based on the first smoothed torque demand; wherein the smoothed torque increase step size is negatively correlated with the current remaining charge of the power battery and the minimum temperature of each individual cell in the battery pack; or, The third determining module is used to determine the second smoothing demand torque of the engine at the current moment based on the original torque increase step size of the engine at the current moment, when the engine demand torque at the current moment is determined to be less than or equal to the torque smoothing critical value, and to determine the compensation torque of the electric motor based on the second smoothing demand torque.

9. A computer device comprising a memory and a processor, wherein the memory stores computer-readable instructions, characterized in that, When the computer-readable instructions are executed by the processor, the processor performs the steps of the smooth control method for engine torque of the hybrid power system as claimed in any one of claims 1 to 7.

10. A storage medium storing computer-readable instructions, characterized in that, When the computer-readable instructions are executed by one or more processors, the one or more processors perform the steps of the smooth control method for engine torque of the hybrid power system as claimed in any one of claims 1 to 7.

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