基于气液转换器的气动汽车动力系统能效优化

Power Efficiency Optimization of Hydro-pneumatic Transformer of Air-powered Automobile

随着能源和环境问题日益严重,基于气液转换器的气动汽车逐渐被关注。然而,以压缩空气为动力来源的气液转换器在工作时能量效率低下,直接影响了气动汽车的发展。设计了一种驱动气动汽车的气液转换器系统,建立数学模型,对气液转换器的工作过程进行仿真,分析了关键结构参数对该系统能效的影响。并搭建基于此气液转换器的汽车动力系统实验平台进行验证,得到优化系统能效的方法,结果表明:当输入压力在0.5~0.55 MPa之间变动时,或者活塞的有效面积比为4~6之间,系统的效率将会超过30%。活塞行程对效率的影响小,随着活塞行程的变化,效率保持在30%几乎不变;活塞行程对输出功率影响大,活塞行程增加时,输出功率下降;输入压力和活塞有效面积比增加时,输出功率也会增加。结果表明:为气液转换器的结构设计和性能优化提供了依据。

With the serious worldwide energy and environmental problems,air-powered vehicle with pneumatic-hydraulic booster has caused more and more attention.However,the power efficiency of the pneumatic-hydraulic booster using compressed air as the power source is low,which directly affects the development of the air-powered vehicle.This paper proposes a new kind of pneumatic-hydraulic transformer system which can drive the vehicle continuously running,and optimizes the power efficiency based on the key structure parameters.The mathematical model is built to simulate the working process of the pneumatic-hydraulic transformer.Next,we establish the test bench to verify the mathematical model.Through simulation we set different values to study the influence of the key parameters on the power efficiency of the system.We can get some conclusions that,when the input compressed air pressure ranges from 0.5~0.55 MPa,or the area ratio of piston ranges from 4~6,the efficiency will exceed 30%.The efficiency nearly keeps constant when the stroke of the piston varies.Whats more,with the increase of input pressure and effective piston area ratio,the output power will be rising.When the pistons stroke increases,the output power decreases a little bit.This paper can be a reference of researches on the design and optimizing of HP power system used on airpowered automobile.