Dynamic Modeling And Simulation Of Inverter Air Conditioning System With Dual-Compressor In Rail Train

With the increase of world population and traffic pressure,there is a growing demand for rail trains.Accompanied by the rise of the quality of human life,people also put forward higher requirements on the comfort of rail trains in summer,while the air conditioning is the main device.Inverter air conditioning with dual-compressor is a new type of air conditioning system adopted by Chinese rail trains nowadays which has the advantages of small volume,energy saving,environmental protection and wide temperature range and so on compared with the single compressor fixed frequency air conditioning.However,due to the fact that this air conditioning system of Chinese rail trains is still under development,the modeling and simulation of this air conditioning system has been rarely found in the literatures.In this paper,we model and simulate the whole refrigeration cycle process systematically in the air conditioning with dual-compressor of the rail trains.Furthermore,we also study the control process of air conditioning system preliminarily.Detailed research contents and main results are shown as follows:1.We conduct the mechanism analysis of compressor,condenser,throttling valve and evaporator of air conditioning system,and conduct the dynamic modeling of every component.At last,we simulate every component based on the model and discuss the results.2.Based on every component model,we build the model of inverter air conditioning system with dual-compressor.Then the steady characteristic simulation and the dynamic characteristic simulation are studied while we analyze the simulation results of its availability.3.We analyze four factors that affecting the cool effect of the air conditioning system of rail trains,including the temperature of evaporating air,the temperature of condensing air,the speed of compressor and the opening degree of throttle valve.The increase in temperature of evaporating air and the decrease in temperature of condensing air can strengthen cooling capacity and coefficient of performance while increasing the power consumption of compressor.The increase in speed of compressor can reduce the coefficient of performance and the increase in opening degree of throttle valve can reduce cooling capacity.All of this would be the important criterion when design air conditioning and chose component.4.On the basis of the model of inverter air conditioning system with dual-compressor,we try to design the control system program.