Optimization method for controlling gear shifting point of gearbox

Abstract

According to the optimization method for controlling the gear shifting point of the gearbox, the gear shifting point of a vehicle is adjusted and optimized according to the actual idle speed value of an engine, and the influence of idle speed increasing on gear shifting in the driving process is avoided. A theoretical gear shifting MAP is obtained through calculation according to the basic idle speed value of the engine, the actual idle speed rotating speed value of the engine is obtained, an idle speed deviation value is obtained by subtracting the theoretically obtained basic idle speed value from the actual idle speed rotating speed value of the engine, the idle speed deviation value is corrected into the theoretical gear shifting MAP, and the corresponding actual gear shifting MAP of the engine is obtained.

Description

Technical Field

[0001] This invention relates to the technical field of gearbox shifting, specifically to an optimization method for controlling gearbox shift points. Background Technology

[0002] Automatic transmission vehicles shift gears according to shift points, including upshifts and downshifts. Current technology uses a conventional shift map (MAP) to mark these shift points. This MAP is calculated based on the engine's base idle speed. When the engine speed matches the shift point in the MAP, the corresponding upshift or downshift is performed. However, during actual driving, when the DPF (diesel particulate filter) is activated, the engine idle speed increases. This higher idle speed makes it easier for the vehicle to trigger upshifts, leading to frequent upshifts. Conversely, the increased idle speed makes it harder to trigger downshifts, making downshifting difficult. In severe cases, if the idle speed exceeds the set downshift MAP, the vehicle may be unable to downshift effectively. Therefore, the existing method of calculating shift points solely based on the engine's base idle speed is not conducive to the scientific and reliable shifting of automatic transmission vehicles. It is necessary to develop an optimized method for controlling transmission shift points. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides an optimization method for controlling the shift points of a transmission. This method adjusts and optimizes the vehicle's shift points based on the actual idle speed of the engine, thus resolving the impact of increased idle speed on shifting during driving.

[0004] An optimization method for controlling the shift points of a transmission is characterized by: calculating a theoretical shift MAP based on the engine's base idle speed value, obtaining the engine's actual idle speed value, subtracting the engine's actual idle speed value from the theoretically obtained base idle speed value to obtain an idle speed offset value, and then correcting the idle speed offset value into the theoretical shift MAP to obtain the corresponding engine's actual shift MAP.

[0005] Its further features are: The same engine has more than one idle speed point. The idle speed point is dynamically adjusted by the engine control unit (EMS) according to the engine status, load and environmental conditions. The actual idle speed value of the engine under different engine status, load and environmental conditions is broadcast by the EMS in the EC1 message of the J1939 protocol, so that the TCU can obtain the actual idle speed value of the engine through the bus message. The theoretical shift MAP is the shift MAP based on idle speed, and its acquisition method includes the following steps: S1 calibrates the engine's base idle speed value, which is the engine's stable speed at normal operating temperature and without any load. S2 calibrates and calculates the shift MAP of other logics based on the calibrated base idle speed value of the engine and the actual needs of the vehicle, including upshifting and downshifting. This MAP is the shift MAP when the engine idle speed is the base idle speed. The shift MAP is based on the theoretical shift MAP. It combines the idle speed value under real-time conditions and the basic idle speed value to obtain the idle speed offset value. Then, the corresponding engine speed value and idle speed offset value of each shift point in the shift MAP are added to obtain the shift MAP under real-time conditions. The shift MAP is updated in real time according to the actual idle speed value of the engine.

[0006] By adopting the above technical solution, the vehicle's shift points are adjusted and optimized based on the actual idle speed of the engine, so that the shift points are adapted to the engine's state, load, and environmental conditions. The adjustment and optimization of the vehicle's shift points based on the actual idle speed of the engine solves the problem of the impact of increased idle speed on shifting during driving. Detailed Implementation

[0007] An optimization method for controlling the shift points of a transmission involves first calculating a theoretical shift MAP based on the engine's baseline idle speed value, then obtaining the engine's actual idle speed value, subtracting the actual idle speed value from the theoretical baseline idle speed value to obtain an idle speed offset value, and then correcting the idle speed offset value into the theoretical shift MAP to obtain the corresponding actual shift MAP for the engine.

[0008] In practice, it includes the following steps: Step a: For the same engine, there may be more than one idle speed point. The idle speed point is dynamically adjusted by the engine control unit (EMS) based on the engine's status, load, and environmental conditions. The actual idle speed value of the engine under different engine statuses, loads, and environmental conditions is broadcast by the EMS in the EC1 message of the J1939 protocol. Thus, the TCU obtains the actual idle speed value of the engine through bus messages. ; Step b, obtain the theoretical shift MAP, which is the shift MAP based on idle speed. The method for obtaining it includes the following steps: Sb1, calibrating the engine's base idle speed value This base idle speed value is the stable speed of the engine when it is at normal operating temperature and under no load (including when the air conditioner and headlights are off); Sb2, based on the calibrated engine's baseline idle speed value Based on the actual needs of the vehicle, other shift MAP calibrations and calculations are performed, including upshifts and downshifts. This MAP is the shift MAP based on the engine idle speed. ; Step c, actual shift MAP correction Sc1, calculate idle speed offset value ; Sc2, shift MAP correction, actual shift. ; Sc3 will actually shift gears. This serves as the actual shift map under the current engine condition, load, and environmental conditions.

[0009] In practice, steps a and b can be interchanged without affecting the use of the optimization method.

[0010] The shift MAP is based on the theoretical shift MAP. It combines the idle speed value under real-time conditions and the basic idle speed value to obtain the idle speed offset value. Then, the corresponding engine speed value and idle speed offset value of each shift point in the shift MAP are added to obtain the shift MAP under real-time conditions. The shift MAP is updated in real time according to the actual idle speed value of the engine.

[0011] It adjusts and optimizes the vehicle's shift points based on the engine's actual idle speed, making the shift points adapt to the engine's state, load, and environmental conditions. By adjusting and optimizing the vehicle's shift points based on the engine's actual idle speed, it solves the problem of increased idle speed affecting shifting during driving.

[0012] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0013] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An optimization method for controlling the shift point of a transmission, characterized in that: The theoretical shift MAP is calculated based on the engine's base idle speed value. The actual idle speed value of the engine is obtained, and the idle speed offset value is obtained by subtracting the theoretical base idle speed value from the actual idle speed value. The idle speed offset value is then corrected into the theoretical shift MAP to obtain the corresponding actual shift MAP of the engine.

2. The optimization method for controlling the shift point of a transmission according to claim 1, characterized in that: The same engine has more than one idle speed point. The idle speed point is dynamically adjusted by the engine control unit (EMS) based on the engine status, load and environmental conditions. The actual idle speed value of the engine under different engine status, load and environmental conditions is broadcast by the EMS in the EC1 message of the J1939 protocol, so that the TCU can obtain the actual idle speed value of the engine through the bus message.

3. The optimization method for controlling the shift point of a transmission according to claim 2, characterized in that: The theoretical shift MAP is the shift MAP based on idle speed, and its acquisition method includes the following steps: S1 calibrates the engine's base idle speed value, which is the engine's stable speed at normal operating temperature and without any load. S2 calibrates and calculates the shift MAP for other logics based on the calibrated base idle speed value of the engine and the actual needs of the vehicle, including upshifting and downshifting. This MAP is the shift MAP when the engine idle speed is the base idle speed.

4. The optimization method for controlling the shift point of a transmission according to claim 3, characterized in that: The shift MAP is based on the theoretical shift MAP. It combines the idle speed value under real-time conditions and the basic idle speed value to obtain the idle speed offset value. Then, the corresponding engine speed value and idle speed offset value of each shift point in the shift MAP are added to obtain the shift MAP under real-time conditions. The shift MAP is updated in real time according to the actual idle speed value of the engine.