Modeling And Control Methods Of Multi-stack Fuel Cell Power Systems For Light Rail Vehicles

With the rapid economic growth and the rapid rise of national economy,environmental pollution is becoming serious increasingly,energy consumption is increasing,fossil cost resources are exhausted increasingly,many countries are vigorously carrying out green energy and renewable energy applications and research.Among the numerous new energy applications,hydrogen energy is the clean,safe,sustainable and efficient,which is regarded as the most promising clean energy in the 21 st century.Modern trams,light rail vehicles and bullet trains,have the advantages of safety,reliability and environmental protection.They are widely used as the transport mode of medium and low traffic volume.It is the new breakthrough to apply the fuel cell power generation system to high-power vehicles.This paper mainly studies the modeling and control method of multi-stack fuel cell power generation systems for light rail vehicles.The main work is as follows:By studying various topological structures of multi-stack fuel cell power generation systems,the advantages and disadvantages of various topologies are analyzed and compared,and the topological structure of multi-stack fuel cell parallel forming fuel cell power generation system is determined by combining the demand characteristics of light rail vehicles under actual operating conditions,which can effectively increase the power level of fuel cell.The hardware design of fuel cell scaling system is established.Based on NiQor converter module,the hardware part is designed.The output voltage is stable in a wide input range,the voltage boost capability is large,the response is quick and the ripple of the input current is small.According to the topological structure of the multi-stack fuel cell power generation systems,based on the Matlab/Simulink simulation platform,the fuel cell stack model,unidirectional DC/DC converter model,electronic load model and control strategy model are established to analyze the parallel operation characteristics of the multi-stack fuel cell and related influencing factors.On the basis of the established model,a efficiency optimization control method of multi-stack parallel fuel cell system is proposed for high voltage and high power applications,considering the efficiency of the whole system including air compressor and other auxiliary engines and the power distribution of multiple reactors.By adaptive power distribution control of PEMFC multi-stack systems,distributing the power required to each stack reasonable.With optimal overall system efficiency as the evaluation index,making the whole multi-stack fuel cell power generation system in the best working state.Make sure that the overall efficiency of the system is optimal,thus ensuring the PEMFC multi-stack fuel cell system with optimal efficiency and stable operation.Finally,the RT-LAB real-time simulation platform is used to test the control method,and compared with other control methods,the advantages of the power adaptive allocation control method are proved.The experimental results show that the power adaptive allocation strategy can ensure the maximum efficiency nearly in the whole range of output power,greatly expand the useful power range,realize the optimization of efficiency in the full power range of multi-stack PEMFC power generation system,and thus significantly improve the performance of high-power vehicles.