Research On Energy Efficiency Test Method For Automotive Hybrid Power System

In a conventional fuel vehicle,the function of the electric power system is to supply electricity required by the electrical equipment.However,with the improvement of automotive bus and the power consumption of vehicle electrical equipment,traditional power supply system can no longer meet the requirements of the current vehicle electrical system.Therefore,the power system is developing toward the direction of intelligent generator management,battery delicacy management and storage battery in parallel with super capacitors hybrid power supply system.The research of hybrid powe r system in the traditional fuel car is becoming the key to the automotive power management.This thesis,which is based on enterprise cooperation projects,studies the energy efficiency,efficiency formula and test methods of automotive hybrid power system.Firstly,through the analysis of the existing automotive power system architecture and its existing problems,the composition of hybrid power system.Secondly,the operating mode of the hybrid power system is analyzed,the efficiency of the hybrid power system is defined,and the efficiency calculation formula is given.The architecture and working mode of the hybrid power system are briefly discussed.Determined the internal and external power relationships of the composite power system.The efficiency of the hybrid power system is defined.The concept of average and instantaneous efficiency of the hybrid power system is proposed.The relations of external power in hybrid power system are analyzed,and the energy source of the hybrid power system is determined.According to the internal power relationship of the hybrid power system,the formula for the efficiency of the hybrid power system is deduced.Then,analyze the test quantity and method for obtaining the two kinds of efficiency test,and give the efficiency test flow in the vehicle environment.For the test of instantaneous efficiency,an orthogonal test scheme was developed based on the calculation method under instantaneous efficiency conditions.The test methods and test schemes of the average efficiency and the instantaneous efficiency are given by the efficiency test formula.Finally,the whole vehicle test platform based on chassis dynamometer was built,and the upper computer acquisition software based on LabVIEW was developed.The average eff iciency and instantaneous efficiency test tests were conducted.The instantaneous efficiency MAP of the composite power supply system of the benchmark vehicle is given,which proves the effectiveness of the efficiency test method in this paper.The research in this thesis is of great significance and application value to formulating the follow-up work strategy of hybrid power system and evaluating the energy efficiency of power system.