Study On Proton Exchange Membrane Fuel Cell Thermal Management System

Looking forward to the world,the diversification of fuel is constantly advancing,and the importance of hydrogen energy is also increasing.As one of the development directions of new energy vehicles in the future,hydrogen fuel cell vehicles have attracted more and more attention from governments and enterprises around the world.Nowadays,there are still many barriers in the promotion of fuel cell vehicles,not only in technology and infrastructure,but also in people's recognition of vehicle performance.For example,the performance of fuel cell vehicles in extreme environment,the fuel cell can work safely and efficiently only under the appropriate temperature,so it is necessary to design a reasonable thermal management scheme to solve the heat dissipation problem of fuel cell in extreme environment.This article is based on the secondary development of a European multi-functional commercial vehicle,designs the vehicle power system and formulates the corresponding energy management strategy according to the vehicle parameters and performance requirements;Through the analysis of the heat production of stacks,motors,power batteries,etc.,the vehicle thermal management plan is formulated,and the thermal management plan is tested,simulated,and optimized.Firstly,the power system is designed based on the real vehicle parameters and performance requirements,and the energy management strategy of the fuel cell vehicle is formulated.Then,the modeling and simulation are carried out based on AMESim and Simulink,and the reliability of the system design and the accuracy of the model are verified through the condition test.Then,according to the heat dissipation requirements of the vehicle,the fuel cell thermal management system,power battery thermal management system,and motor thermal management system are designed,modeled,model verified,and performance simulation;Finally,we focused on the fuel cell thermal management system and optimized it for system defects.In this paper,the design of thermal management system in extreme environment and the optimization of fuel cell thermal management system are taken as innovation points to achieve the normal heat dissipation requirements of vehicle components.In this paper,a PTC heater is added to the thermal management loop of the stack and the power battery to realize the rapid temperature rise in the low temperature environment;By adding the liquid cooling branch of the power battery on the basis of the air-conditioning refrigeration system,the normal heat dissipation of the high temperature environment of the power battery is realized;In order to solve the defects of frequent start-up of pumps and fans and frequent change of rotating speed in fuel cell thermal management system,the model predictive control based on state space is used to optimize the design.By establishing mathematical model and designing model predictive controller based on state space,the purpose of stabilizing system temperature and reducing parasitic loss is realized,and the disadvantages of hysteresis and overshoot of temperature control system are avoided.Through simulation analysis,the optimized cooling system can save 12.5% energy.