ACC (adaptive cruise control) system and method for four-wheel hub motor electric vehicle

Abstract

The invention discloses an ACC (adaptive cruise control) system for a four-wheel hub motor electric vehicle, which comprises: taking the four-wheel hub motor electric vehicle as an object of study on ACC (adaptive cruise control), the invention provides a mode switching control method considering the difference between theoretic safe distance and actual distance and relative velocity of two vehicles. According to the method, ACC into a preceding vehicle following mode, a constant velocity cruise mode and a uniform velocity travelling mode; an ACC controller comprising a theoretic safe distance algorithm, a driving torque control algorithm and a braking torque control algorithm, is designed; braking energy is recycled through regenerative braking; a control strategy is verified experimentally based on typical working conditions designed by a driving simulator experiment table. The invention discloses an ACC method for a four-wheel hub motor electric vehicle. The system and the method have the characteristics of being high in operational security and stability, accurate in control, reasonable in torque distribution, and effective in energy-saving control.

Description

technical field [0001] The invention relates to the field of safety assisted driving, in particular to an adaptive cruise control system and method for an electric vehicle with four-wheel hub motors. Background technique [0002] Adaptive cruise control (ACC) is a safety-assisted driving system developed on the basis of constant-speed cruise control. It belongs to the active safety control of automobiles and is a component of advanced driver-assistance systems. It has become a research hotspot at home and abroad. In the prior art, the adaptive cruise control system (ACC) mainly has the following situations: (1) based on fuzzy control, a kind of adaptive cruise according to the driver's manipulation habit of accelerator pedal and brake pedal is proposed; (2) ) proposed a linear car-following algorithm based on the driver's steady-state car-following characteristics, designed a speed closed-loop control strategy based on an inverse lookup table, and controlled the vehicle's ad...

AI Technical Summary

Problems solved by technology

In the prior art, the adaptive cruise control system (ACC) mainly has the following situations: (1) based on fuzzy control, a kind of adaptive cruise according to the driver's manipulation habit of accelerator pedal and brake pedal is proposed; (2) ) proposes a linear car-following algorithm based on the driver's steady-state car-following characteristics, and designs a speed closed-loop control strategy based on an inverse lookup table, which controls the vehicle's adaptive cruise through incremental PID; (3) establishes a vehicle driving model and system Based on the dynamic model, the vehicle speed criterion can be derived to judge and identify the current area of ​​the car, and the division area can be adjusted hierarchically; (4) The applicability of the current adaptive cruise algorithm is checked by comparing the data collected from the simulation model and the real vehicle; (5) adopt model predictive control (MPC) method, design an easy-to-adjust hybrid controller for ACC application, and carry out software simulation and system evaluation; The distance between the vehicle and the target vehicle is preset as a fixed value, and the relationship between the inter-vehicle distance and the relative speed of the two vehicles is less considered. Such adaptive cruise control will be inconsistent with the driver's real expectations. For example, when the distance between the two vehicles is less than the preset When setting the distance, even if the speed of the vehicle in front is faster than the speed of the vehicle, the vehicle will still brake and decelerate to ensure the preset distance

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