EPS power start-stop control method for pickup trucks

Abstract

The invention discloses an EPS power-assisted start-stop control method for a pickup truck, which utilizes the existing engine start-stop system, ABS anti-lock braking system / ESP body stability system, SAS steering wheel angle sensor, EPS system and ECU engine control system on the vehicle, and realizes multi-mode, full-condition engine speed and vehicle speed step-by-step power-assisted adjustment through the automatic start-stop control strategy of the invention without adding other hardware equipment and wiring harness connection, thereby ensuring driving steering comfort, further reducing vehicle fuel consumption, simplifying the system, and saving vehicle layout space. The invention outputs zero torque in the EPS at the moment of vehicle startup, has no effect on the 12V battery of the vehicle, and the vehicle startup is safe and reliable.

Description

Technical Field

[0001] The invention relates to the field of automobile power assistance research, and in particular to an EPS power assistance start-stop control method for a pickup truck. Background Art

[0002] At present, the requirements for vehicle fuel consumption are getting higher and higher, the stability of vehicle starting is becoming more and more important, the requirements for driving comfort are getting higher and higher, and the comfort of steering control is very important in the driving comfort of the whole vehicle. EPS is a high-power component on the car. When EPS is started, it will affect the battery voltage of the whole vehicle, and the control of the car steering is related to the safety of the whole vehicle driving. Therefore, the control of the car power start and stop is very important. Poor control of the car power start and stop will cause the fuel consumption of the whole vehicle to increase, and at the same time, it will cause the driving comfort of the whole vehicle to be poor.

[0003] The existing EPS power start-stop system for vehicles is expensive and requires the addition of a power start-stop hardware control system. The control logic is simple and cannot cover all vehicle operating conditions, which reduces driving comfort and leads to high fuel consumption. In addition, when the vehicle starts, the EPS starts with maximum torque, which will cause the 12V of the vehicle battery to drop instantly, which can easily cause other vehicle components to fail to start, creating safety hazards. Summary of the invention

[0004] The present invention aims to provide an EPS power-assisted start-stop control method for a pickup truck.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] The EPS power-assisted start-stop control method for pickup trucks of the present invention is divided into four modes, namely, standard mode, stop mode, power-assisted mode 1 and power-assisted mode 2. In the standard mode, the engine is started and EPS normally assists; in the stop mode, the engine is turned off, the vehicle stops, and EPS power assist stops; in the power-assisted mode 1, EPS outputs torque-down assist; in the power-assisted mode 2, EPS outputs torque-up assist.

[0007] When the engine is turned off and EPS power assist stops, if it is detected that the current engine speed is greater than the engine speed that allows EPS to start power assist, EPS enters the standard mode; if it is detected that the current vehicle speed is greater than the vehicle speed that stops EPS power assist and less than the vehicle speed that allows EPS to start power assist, EPS enters power assist mode 2;

[0008] When the EPS is in the power-assistance mode 2, if it is detected that the current vehicle speed is less than or equal to the vehicle speed at which the EPS power-assistance stops, the EPS enters the stop mode; if it is detected that the current vehicle speed is greater than or equal to the vehicle speed at which the EPS power-assistance is allowed to start, the EPS enters the standard mode;

[0009] When the EPS is in the standard mode, if it is detected that the current engine speed is less than or equal to the engine speed that allows the EPS to start the power assist, the EPS enters the power assist mode 1;

[0010] When EPS is in the power-assist mode 1, when it is detected that the current vehicle speed is less than or equal to the speed at which EPS power-assist stops, EPS enters the stop mode; when it is detected that the current engine speed is greater than the engine speed that allows EPS to start power-assist, EPS enters the standard mode.

[0011] The invention has the advantage of utilizing the existing engine start-stop system, ABS anti-lock braking system / ESP body stability system, SAS steering wheel angle sensor, EPS system and ECU engine control system on the vehicle, and realizing multi-mode, full-condition engine speed and vehicle speed step-by-step adjustment assistance without adding other hardware equipment and wiring harness connection through the automatic start-stop control strategy of the invention, thereby ensuring driving steering comfort, further reducing vehicle fuel consumption, simplifying the system, and saving vehicle layout space. The invention outputs zero torque in the EPS at the moment of vehicle startup, has no effect on the 12V battery of the vehicle, and the vehicle startup is safe and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is the system module used in the method of the present invention.

[0013] Figure 2 Schematic diagram of mode switching of the method of the present invention. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] like Figure 1 As shown, the EPS power-assisted start-stop control method for pickup trucks described in the present invention utilizes the existing engine start-stop system, ABS anti-lock braking system or ESP body stability system, SAS steering wheel angle sensor, EPS system and ECU engine control system on the vehicle to realize the power-assisted start-stop of the vehicle through control logic. The inventor divides the power-assisted start-stop into four modes, namely standard mode, stop mode, power-assisted mode 1 and power-assisted mode 2. In standard mode, the engine starts and EPS assists normally; in stop mode, the engine is turned off, the vehicle stops, and EPS assists stop; in power-assisted mode 1, EPS outputs torque-down assist; in power-assisted mode 2, EPS outputs torque-up assist.

[0016] The specific switching process of the power start-stop mode is as follows: Figure 2 As shown, number ① indicates that when the engine is turned off and the EPS power assist stops, if it is detected that the current engine speed is greater than the engine speed that allows EPS to start power assist, EPS enters the standard mode; number ② indicates that when the engine is turned off and the EPS power assist stops, if it is detected that the current vehicle speed is greater than the vehicle speed that allows EPS to start power assist and less than the vehicle speed that allows EPS to start power assist, EPS enters power assist mode 2;

[0017] Sequence number ④ indicates that when the EPS is in the power-assist mode 2, if it is detected that the current vehicle speed is less than or equal to the vehicle speed at which the EPS power-assist stops, the EPS enters the stop mode; Sequence number ③ indicates that when the EPS is in the power-assist mode 2, if it is detected that the current vehicle speed is greater than or equal to the vehicle speed at which the EPS is allowed to start power-assist, the EPS enters the standard mode;

[0018] Sequence number ⑤ indicates that when the EPS is in the standard mode, if it is detected that the current engine speed is less than or equal to the engine speed that allows the EPS to start the power assist, the EPS enters the power assist mode 1;

[0019] Serial number ⑥ indicates that when EPS is in the power-assist mode 1, if it is detected that the current vehicle speed is less than or equal to the speed at which EPS power-assist stops, EPS enters the stop mode; Serial number ⑦ indicates that when EPS is in the power-assist mode 1, if it is detected that the current engine speed is greater than the engine speed that allows EPS to start power-assist, EPS enters the standard mode.

[0020] In the present invention, when EPS outputs torque-raising assistance or torque-reducing assistance, it increases the assistance output step by step with a variable slope, or reduces the assistance output step by step with a variable slope, thereby ensuring the safety and comfort of vehicle driving during the torque raising and lowering process.

[0021] In the present invention, the vehicle speed at which EPS power assistance stops, the engine speed at which EPS power assistance is allowed to start, and the vehicle speed at which EPS power assistance is allowed to start are all calibrable values, that is, they can be calibrated according to different vehicle models and driving comfort to adapt to more vehicle models.

[0022] The present invention does not increase the hardware control system, saves the control hardware cost, has a simple and flexible system design, and has a complete power-assisted start-stop control strategy, which divides the power-assisted start-stop into multiple modes to cover the power-assisted start and stop under various operating conditions of the whole vehicle. The system has the advantages of stable and reliable start-stop and safe steering of the whole vehicle. At the same time, the system reduces the fuel consumption of the whole vehicle system, making the whole vehicle more energy-saving and environmentally friendly.

Claims

1. A pickup truck EPS power start-stop control method, characterized in that: When the engine is turned off and EPS power assistance stops, if it is detected that the current engine speed is greater than the engine speed that allows EPS to start power assistance, EPS enters the standard mode; When it is detected that the current vehicle speed is greater than the speed at which EPS power assistance stops and less than the speed at which EPS power assistance is allowed to start, EPS enters power assistance mode 2; When the EPS is in the power-assistance mode 2, if it is detected that the current vehicle speed is less than or equal to the vehicle speed at which the EPS power-assistance stops, the EPS enters the stop mode; if it is detected that the current vehicle speed is greater than or equal to the vehicle speed at which the EPS power-assistance is allowed to start, the EPS enters the standard mode; When the EPS is in the standard mode, if it is detected that the current engine speed is less than or equal to the engine speed that allows the EPS to start the power assist, the EPS enters the power assist mode 1; When the EPS is in the power-assist mode 1, if it is detected that the current vehicle speed is less than or equal to the vehicle speed at which the EPS power-assist stops, the EPS enters the stop mode; When it is detected that the current engine speed is greater than the engine speed that allows EPS to start assist, EPS enters the standard mode; In the standard mode, the engine starts and EPS assists normally; In the stop mode, the engine is turned off, the vehicle is stopped, and the EPS assist is stopped; In the power assist mode 1, the EPS outputs torque reduction power assist; In the power assist mode 2, EPS outputs increased torque assistance.

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