Research On Coordinated Control Of Regenerative Braking And Anti-lock Braking System Of Hydraulic Hybrid Vehicle

With the rapid economic development,the oil crisis is getting worse and the environmental pollution is getting worse.Energy-saving and new energy vehicles have become the focus and hotpot of the automotive industry research.Hydraulic hybrid car is a kind of energy-saving car,which has its unique advantages.The hydraulic hybrid power system has more advantages in volume and weight.Compared with the battery pack,the layout of the hydraulic energy storage system is more compact and the volume is smaller.Compared with power batteries such as nickel-metal hydraulic,lithium batteries,etc.,the hydraulic hybrid power storage system uses compressed nitrogen,which has the advantages of easier recovery and no pollution.There is no need to set up a separate management system for hydraulic pump / motor and accumulator,which reduces the difficulty of vehicle control and reduces the development cost of the vehicle.Regenerative braking is the main energy-saving way for hydraulic hybrid vehicles.The intervention of hydraulic regenerative braking will affect the work of the anti-lock brake system.This paper studies the coordinated control algorithm of hydraulic regenerative braking system and anti-lock braking system for parallel hydraulic hybrid vehicles.The main research contents of this article are:(1)Based on a parallel hydraulic hybrid vehicle,establish a tire model,a slip rate model,a hydraulic pump / motor model,a hydraulic pump / motor swash plate opening adjustment model,a hydraulic accumulator model,a brake model,and a brake wheel cylinder model,Anti-lock brake system model,etc.,provide a theoretical basis for the proposed control strategy and simulation analysis.(2)A two-parameter threshold anti-lock braking system control algorithm based on slip rate-road adhesion coefficient is proposed.Based on the anti-lock brake system model,the stability analysis of the system is carried out,and the mechanism of the influence of the control parameter threshold of the anti-lock brake system on the stability of the anti-lock brake system is obtained.System control strategy.(3)The characteristics of the hydraulic regenerative braking system and the workingcharacteristics of the hydraulic pump / motor are analyzed.According to the characteristics of hydraulic hybrid power system,a coordinated control algorithm for parallel hydraulic hybrid vehicle regenerative braking system and anti-lock brake system is proposed.After the anti-lock brake system is triggered,the hydraulic regenerative braking force provided by the hydraulic pump / motor and the braking force of the mechanical braking system are coordinated to control the braking energy recovery rate,while keeping the hydraulic hybrid vehicle in good control.Dynamic performance.(4)Build parallel hydraulic hybrid electric vehicle simulation model,regenerative braking system simulation model,anti-lock brake system simulation model and coordinated control algorithm model in Matlab / Simulink.Simulation analysis under typical working conditions proves the control effect of the anti-lock braking control algorithm and coordinated control algorithm proposed in this paper.