Study On Integrated Chassis Control With Multiple Objectives For Electric Vehicle

At present, under the trend of "Safety, energy saving and environmental protection", the electrification process brought by electric vehicles is accelerating. The new generation vehicle chassis system with the electronic control as the core, which is based on the electric drive, electric brake and electric steering, has become the trend of the automobile industry in the future.The emergence and development of the new generation electric vehicle chassis system provides a good opportunity for the intelligent integration of vehicle chassis system. At the same time, it also brings more challenges, for instance, the redundancy degree of the system is higher, the coupling is more serious, the control objectives are more complicated and various. So it’s more urgent to accomplish the integrated chassis control with multiple objectives for electric vehicle. In this paper, it proposes the integrated chassis control strategy with multiple objectives for the electric vehicles with four wheel independent control based the National Natural Science Fund Project and the "863" project. It design integrated control architecture for electric vehicle chassis, develop the integrated control algorithm of feedforward and feedback, and proposed the control allocation strategy with multiple objectives. This paper also dose the off-line simulation and hardware in the loop test to analyze and verify the control strategy under the platform with MATLAB/Simulink and Car Sim software and independent designed rapid control prototyping experiment platform based on double d SPACE(1) Construct the integrated chassis control architecture for electric vehicle, including electronic and electrical hardware architecture and integrated chassis control architecture of dynamics.The design of electrical and electronic architecture of electric vehicles makes sure the layout of hardware system, communication system architecture and electrical and electronic architecture and so on. Based on the idea of hierarchical structure and function classification, the integrated chassis control system of dynamics is divided into the perception layer, control command layer, control distribution layer and execution layer.(2) Design the the integrated chassis control strategy with multiple objectives for the electric vehicles. In the perception layer, it identifies driver’s intention based on reference model. In the command layer, it computes the generalized force of vehicle body with PI feedback control and feedforward control based on vehicle model of three degree freedom. In the control distribution layer, it completes the tire force distribution with multiple objectives based on the approximation algorithm of penalty function. The execution layer converts the tire force to the specific force of chassis actuator.(3) Construct the offline simulation platform based on MATLAB/Simulink and Car Sim software and the control strategy is tested under the typical working conditions. In offline simulation environment, the controlled performance of vehicle dynamics, economy, handling stability is verified.(4) Build the rapid control prototyping experiment platform based on double d SPACE. The controlled vehicle model and control algorithm are downloaded to two d SPACE prototype controllers. The platform uses the CAN bus communication. In the typical operating conditions, the real-time control effect of the control strategy is verified with rapid control prototype test. The results show that the real-time response of the integrated chassis control system with multiple objectives for the electric vehicles is good and it improves the overall performance of the electric vehicle significantly.