Research On Control Strategy Of High Power Fuel Cell Engine Air Supply For Heavy-duty Truck

Facing the shortage of traditional fossil energy and the current situation of pollutant emission,the research and development of new energy vehicles has become the mainstream direction of the development of automobile industry.Because of the advantages of zero emission and long endurance mileage,fuel cell vehicles are widely concerned because of their lower cost compared with pure electric vehicles.As an important part of the fuel cell vehicle power system,the fuel cell engine needs to respond smoothly and quickly and meet the power demand.The air supply system is responsible for delivering the air in the atmosphere to the fuel cell cathode to participate in the electrochemical reaction,providing sufficient air flow to avoid oxygen starvation,and preventing the impact of gas on the proton exchange membrane which is the key to improve the performance and life span of fuel cell engeine.In this paper,the gas supply control strategy of the air supply system of high power fuel cell engine for heavy truck is studied.The main research contents are as follows:According to the power requirements and system scheme of the fuel cell heavy trucks,the matching calculation of the important components such as the electric reactor and centrifugal air compressor inside the fuel cell engine is carried out.The fuel cell engine simulation model including the electric reactor,air compressor and electronic throttle is established in Matlab/Simulink,which provides a simulation platform for the follow-up air supply control strategy research.This paper introduces the structure of centrifugal air compressor and electronic throttle,and analyzes the influence of their working conditions on the output voltage of fuel cell.To explore the influence of the change of peroxide ratio on the net output power of fuel cell engine under different loads,and to obtain the optimal peroxide ratio based on the maximum output net power under different loads.Combined with the anti surge requirements of centrifugal air compressor and map of centrifugal air compressor,the working demand curve of air compressor is determined.Based on the relationship between the input voltage of the centrifugal air compressor and the air flow at the cathode inlet of the fuel cell engine,a feedforward PID control strategy for the air supply system is proposed.The internal model decoupling control strategy and the improved Butterworth filter internal model decoupling control strategy are proposed respectively for the independent and precise control of air flow and pressure at the entrance of the reactor.It solves the problem of the interaction between air flow and pressure control,and the poor response stability of air flow loop.It has good robustness,and it is still applicable in the case of small-scale model mismatch.It has the advantages of multiple adjustable parameters and can meet different use needs.The hardware in the loop simulation test platform is built based on TC1782 development board and NI veristandard platform,and the monitoring interface is developed in Veri Stand software to verify the internal model decoupling control strategy of fuel cell engine air supply system.