Research On Fusion Temperature Control Strategy Of PEMFC Thermal Management System Based On Feedforward

Proton exchange membrane fuel cell(PEMFC)is a low-temperature fuel cell,which has the advantages of clean and pollution-free,high efficiency,high power density,and fast start-up time.It is widely used in electric vehicles,backup power sources,etc.The field is the research focus of the new energy field.In practical applications,temperature is one of the important parameters that affects the performance of PEMFC.A reasonable temperature control strategy is the key to ensuring the optimal working temperature of PEMFC and improving the output characteristics and life of PEMFC.However,improper temperature control will reduce the activity of the catalyst and even cause PEMFC fails,causing a safety accident.Therefore,studying the temperature control strategy of PEMFC thermal management system has important theoretical and practical significance.In this thesis,a PEMFC thermal management system for a hydrogen fuel truck is taken as the research object,and the temperature control strategy of the PEMFC thermal management system is researched.This thesis takes the temperature characteristics of PEMFC as the starting point,and analyzes the current research status of various aspects of PEMFC thermal management system to clarify the control basis of temperature control system.Based on the working principle and experimental data of PEMFC,a dynamic model of PEMFC was built,and the influence of temperature on the output characteristics of PEMFC was analyzed accordingly.A transient simulation platform for the PEMFC thermal management system was established using GT-SUITE and calibrated based on the PEMFC bench test,which provided a model basis for the development of a temperature control strategy.For the PEMFC thermal management system,this thesis adopts the minimum power consumption and temperature control accuracy of the electrical accessories of the cooling system as the optimization and control objectives,and designs the MAP feedforward invariant,with feedback as three fusion control strategies to improve PID control,fuzzy control and variable domain fuzzy control,respectively,and proves their feasibility through theoretical analysis.Based on the load current disturbance and the C-WTVC transient test conditions of commercial vehicles,the temperature control effects of three different fusioncontrol strategies were simulated and analyzed.The results show that all three fusion control strategies can control the temperature deviation of PEMFC inlet coolant within ±1 K and the temperature difference of PEMFC inlet and outlet coolant within 4 K.Among them,the integrated control effect of MAP feedforward fusion variable domain fuzzy control is the best,and compared with MAP feedforward fuzzy control,the temperature of PEMFC inlet coolant and the temperature difference of inlet and outlet coolant are reduced by 42.1% and 10.8%,respectively,and the total adjustment time is reduced by 25%,while the total power consumption of electrical accessories is reduced by 4.62% based on the guaranteed temperature control effect.In addition,considering the role of external factors,based on the analysis of control performance,simulation tests were conducted using MAP fusion variable domain fuzzy control as an example.The results show that this strategy can suppress the influence of ambient temperature and lateral wind speed in the overall trend,quickly respond to changes in working conditions and follow the target temperature,and control the temperature deviation of PEMFC inlet coolant at 333.15 ± 2 K and the temperature difference of inlet and outlet coolant at 6 K,while reducing the total power loss of electrical accessories and improving the efficiency of PEMFC.