Optimization Design Of Electric Vehicles With Electro-hydraulic Brake System Based EHB

Under the dual pressure of the current energy crisis and environmental protection, theproblem of electric car’s regenerative braking energy recovery becomes particularly important, andthe braking technology for electric vehicles becomes a hot topic. This paper proposed the idealbrake force distribution control strategies and the composite electro-hydraulic brake system (EHB)is designed for pure electric vehicles, and a composite EHB electro-hydraulic brake system testbench is built. EHB is called electronic hydraulic braking system, which is a kind of wire brakingsystem. Hydraulic braking force of the front and rear wheels can be real-time controlled by theEHB system, which provide hardware conditions for ideal brake force distribution controlstrategies.In this paper, electro-hydraulic braking system not only maximized the regenerative brakingenergy recovery but also ensured the security of automotive brake. It was important for thedevelopment of electric vehicles braking technology. The main work as follows:(1) The structural designing of EHB system based on EHB as well as the model selection ofthe components and the analysis of working principle were completed. Following mathematicalmodels of the motor and a solenoid valve of the hydraulic brake system were established. And themodels of motor and solenoid valve were built in AMESim.(2) The ideal brake force distribution control strategies were proposed based on the EHBsystem.Analysising the constraints condition of braking: brake regulatory, the motorcharacteristics, the braking stability and braking comfort constraints. Finally, the software ofMATLAB/simulink was used in building the Electro-hydraulic brake simulation model. It provedthat this braking system had the higher energy recovery efficiency, which provided a theoreticalbasis for bench structures.(3) The braking feeling was considered in this paper, and analyzed the Electro-hydraulicbrake system’s influence on the braking feeling. Then the braking feel optimizing controlstrategies had been proposed. Last we established simulink control model and completed a jointsimulation with the AMESim motor and EHB system. We got the brake feeling optimizationresults to provide a basis for the experiment.(4) Electric vehicles semi-physical test bench of the Electro-hydraulic braking system was setup. The hardware design was divided into the test bench, hydraulic system and controllerhardware system design. The software part was divided into the designing of the host computerand the next machine. Then, experimental study of Electro-hydraulic brake subsequently wascompleted. The experiment records composite braking effects and reflects characteristics of EHB. It proved the feasibility of the Electro-hydraulic brake.