| Compared to traditional vehicle, the most advantage of the hybrid electronic vehicle (HEV) is wasting less energy and protecting environment HEV can convert the energy of a moving vehicle into chemical energy and put it into battery, which can be used later.Energy sources and environment are indispensable to human being, but vehicle safety is the most important. ABS (anti-lock braking system), as the base of the other more advantage safety systems such as ESP (electronic stability program has been used widely, and still has much more place to be developed. IN this paper we will talk about how to corporate regenerating braking system and ABS, in order to economize energy and safety.In chapter one, the history and present status of the HEV and ABS are discussed; the principal of HEV and ABS are illuminated also; the contents of the dissertation are put forward.In chapter two, the braking principle of traditional vehicle and regenerating braking principle of HEV are discussed, and how to distributing the braking force between front axle and rear axle is also discussed. Illustrated the theory of double-axle parallel HEV, and discussed the braking system how to work in three work conditions: mechanic-friction brake, regenerating brake, united break.In chapter three, put forward the require for HEV braking system, mainlyanalyses the components of the HEV. The type of HEV used is parallel double-axle HEV, because most of the traditional city bus use air pressure braking system to brake, the HEV braking system discussed in this paper is the same as the traditional vehicle. The braking system used in this paper is able to control it's air pressure to change with the driver's requirement. Air pressure sensor can transfer the pressure signal to ECU, and then ECU make a judgment according to the program built in ECU to regulate the pressure of braking air chamber through the ABS valve.In chapter four, put forward the most energy regenerating brake system, which can recycle that moving energy of moving vehicle as much as possible, and the torque produced by brake system is also regulated as the stroke of the brake pedal. When brake strength is over 0.7 or the slip of any wheel is over 0.20 the ABS start to work to prevent any wheel locking, which can keep the vehicle stable, and shorten brake distance.In chapter five, models such as vehicle dynamic model, brake model, tire model, motor model, battery model, brake pedal model are setup. Most of those models are non-linear, which can bring some difficulty for building models, so some of those models must be simplified. There is delay in those models, so which must be considered so as to approach the real model. In chapter six, the simulation of two control strategy mentioned in chapter four are completed, through the result of the simulations, can reach the followingconclusions:1. Under lower brake strength condition, the most energy recycling strategy can recycle much more energy than the ideal brake force distributed on front and rear axle strategy.2. Under higher brake strength condition, they recycle the same energy , because both of the strategies can utilize the same regenerating brake fore ,and the stop time is also same, the SOC change of the batter is same.3.When brake pedal move fast down or the brake strength is over 0.7,the regenerating brake system quits out, all the brake force is applied by air pressure brake, meanwhile ABS start to work.In chapter seven, the summary and conclusion of the dissertation.is written, illuminated the influence of the research on regenerating brake system and ABS on the development of future HEV and EV...
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