基于道路循环工况的燃料电池空压机瞬态性能试验研究

Experimental Study on Transient Performance of Fuel Cell Air Compressor Based on Road Test Cycle Conditions

燃料电池空压机的动态工作特性直接决定了燃料电池系统的实际工作性能。为通过试验系统地分析空压机的瞬态性能变化规律,搭建了空压机动态性能测试台,设计了一种可反映空压机真实工作特征的瞬态测试工况,分析了单个瞬态测试循环下空压机性能与运行参数的变化特性。结果表明,空压机在瞬态工况下的运行点主要位于稳态脉谱图的中间窄带部分,处于较高效率的工作区间;空压机的进出口流量差受压比和温度比共同影响而剧烈波动,且在高转速区域流量差较大,主要介于3.5~8.5 m~3/h之间;高转速区域最大功率消耗达到5.6 kW,造成较大的寄生损失,而出口温度变化的敏感性较低;当空压机转速由9750 r/min快速降低至4450 r/min时,流量变化存在约2 s的滞后。

The real operating performance of fuel cell system directly depends on the dynamic workingcharacteristics of its air compressor. In order to systematically analyze the changing law of the transient performanceof air compressor by testing,a dynamic performance test bench for the air compressor of fuel cell is built,and a tran-sient test condition reflecting the real operating characteristics of air compressor is devised,with which the perfor-mance of air compressor and the changing characteristics of its operating parameters under a single transient test cy-cle are analyzed. The results show that the operating points of air compressor in transient condition are mainly locat-ed in the middle narrow band,i.e. a high-efficiency working zone in the steady-state performance map. The inlet andoutlet flow-rate difference of air compressor fluctuates drastically due to the joint-influence of pressure ratio and tem-perature ratio,with a larger flow-rate difference of 3.5~8.5 m~3/h in high speed zone. The maximum power consumedin high-speed zone is up to 5.6 kW,causing a large parasitic loss,but its sensibility to outlet temperature change isrelatively low. When the speed of air compressor sharply lowers from 9 750 r/min to 4 450 r/min,the change of flowrate has a time lag of about 2 s.