Cooling Performance Research Of Air Conditioning System In A Hybrid Electric Vehicle

Under the background of the problem of carbon emission of fuel vehicles and the fact that the existing power battery technology is not enough to meet the needs of pure electric life.In order to ensure the thermal comfort in the occupant cabin,the economy of the hybrid electric vehicle and the thermal safety of power batteries,the refrigeration performance matching of hybrid electric vehicle air conditioning system has been widely concerned.This article relies on a hybrid electric vehicle national project of the China Automotive Engineering Research Institute.The vehicle environmental cabin test platform and the KULI 1D numerical simulation platform are used to carry out research on the cooling performance of the air conditioning system from the system level.By improving the matching degree of components of the air conditioning system,Aimed at improve the cooling performance,while exploring the potential of reducing energy consumption of the air conditioning system.The main research contents of this article are as follows:1.Analyze the working principle and component composition of the hybrid vehicle air-conditioning system in this subject,and measure the structural parameters of the components contained in the air-conditioning system of the test vehicle and perform individual performance tests on them.Based on thermodynamic principles,a modular single-unit simulation model was built on the KULI simulation platform,and verified to meet the accuracy requirements.It lays the foundation for the establishment of the simulation model of cooperative cooling between the passenger compartment and the battery pack.2.A simulation model of the air-conditioning system is built and is verified by the vehicle test.On the basis of the single model in the first part,the refrigerant piping structure parameters between the components of the air-conditioning system are measured according to the spatial layout relationship of the test vehicle,and the numerical simulation model of the cooling of the passenger compartment and battery pack system of the hybrid air-conditioning system is built and calculated.According to the test requirements and safety monitoring requirements,environmental simulation tests are carried out on the entire vehicle,and the system cooling performance simulation model built meets the requirements of engineering applications.3.Select the effective speed of the compressor,the air volume of the blower,and the air intake volume of the front-end module as the input variables of the system coolingperformance research.The sensitivity study of the influence of a single control parameter on the cooling performance of the air conditioning system was carried out under low-speed,medium-speed and high-speed steady-state conditions,and the parameter setting range and cooling performance of each part in the system with the best matching were obtained.The correlation sensitivity to each input variable.4.In order to reduce the contradiction between the increased energy consumption of the passenger compartment and the economy of the air-conditioning system,based on the performance sensitivity study,the correlation sensitivity of the air-conditioning system energy consumption and a single control parameter under the corresponding working conditions was developed.the study.The parameter setting range of each component in the system to minimize the energy consumption of the air-conditioning system is obtained.5.Combined with the research of the parameter setting of the system's single parts and components on the cooling performance sensitivity and the energy consumption of the air conditioning system,a comprehensive analysis of the optimal parameter settings of each part and component is carried out.By optimizing the parameters that are sensitive to performance changes but inert to energy consumption,eight sets of component parameter matching combinations are proposed to simulate the cooling performance of the air conditioning system,so as to reduce the energy consumption of the air conditioning system and improve the cooling performance.