太阳能耦合燃料电池联供系统余热回收的运行参数模拟研究

Simulation of operation parameters for waste heat recovery of solar coupled fuel cell cogeneration system

该文将太阳能与燃料电池相结合,构建太阳能耦合质子交换膜燃料电池的联供系统(proton exchange membranefuel cell,PEMFC)。试验与仿真研究太阳能耦合质子交换膜燃料电池联供系统余热回收的运行参数。试验结果表明:在低温太阳能集热器/空气源热泵热水系统中,储热水箱平均温度为45.55℃,热泵运行温度设定为40~45℃。仿真结果表明:增加PEMFC电堆单电池个数及氢气燃料分压力,可有效提高PEMFC电堆输出电压。提高PEMFC电堆的输出电压及电流的同时,电堆的运行温度随之降低,同时也相应的延长了PEMFC电堆的启动时间。PEMFC电堆循环冷却水进出口温度为45~55℃,当PEMFC电堆循环冷却水进出口温度为50~55℃时,太阳能冷却水进出口温度为40~45℃,PEMFC电堆的运行温度为80.47℃,氢气反应速率为0.015 4 mol/s,板式换热器热效率的合理区间为0.5~0.9。试验及仿真研究结果表明,40~45℃的低温太阳能集热器/空气源热泵热水系统,可连续不断地吸收PEMFC循环冷却水热量,确保联供系统正常运行。

In this paper,the solar coupled proton exchange membrane fuel cell(PEMFC)cogeneration system was constructed by combining solar energy with fuel cell in order to realize multi-energy complementary utilization with storing solar energy in another energy source for user at night and cloudy day.The observation stations were set up to measure solar meteorological parameters day and night according to the test requirements of solar meteorological parameters in the heating and power cogeneration system.The test platform of low temperature solar collectors/air source heat pump hot water system was set up to study operation parameters of hot water system.The simulation models of proton exchange membrane fuel cell(PEMFC)and solar cooling water were established by using Matlab/Simulink simulation software.The simulation results showed that PEMFC stacks output voltage could be effectively raised by increasing the number of single cell and hydrogen partial pressure.PEMFC stacks operation temperature could be cut down by increasing the PEMFC stack output voltage and current but it also prolonged the PEMFC stack start-up time.The inlet and outlet temperature of circulation cooling water for PEMFC stacks was 45-55℃.When inlet and outlet temperature of circulation cooling water for PEMFC stacks was 50-55℃,the inlet and outlet temperature of solar cooling water was 40-45℃,the operation temperature for PEMFC stacks was 80.47℃,hydrogen reaction rate was 0.015 4 mol/s,and the reasonable range of heat efficiency in plate heat exchanger was 0.5-0.9.The experimental results showed that the average temperature of water tank was 45.55℃and the operation temperature of the heat pump was 40 to 45℃in low temperature solar collectors/air source heat pump hot water system.The variation interval of the total average temperature for the low temperature solar collectors/air source heat pump hot water system was 44.24 to 46.94℃during the worst test period of solar energy environment in winter snow day.The feasibility of solar circulation cooling water was verified by experimental result that was accordance with circulation cooling water temperature interval of proton exchange membrane fuel cell.The study results of experiment and simulation showed that the low temperature solar collectors/air source heat pump hot water system which control temperature was 40-45℃,which can continuously absorb thermal energy of circulation cooling water in proton exchange membrane fuel cell and ensure the normal operation of cogeneration system.