Research On Power Distribution Control Strategy Of Hybrid Power Coupling System Based On Optimal On Optimal Efficiency

With the increasingly serious problems of environmental pollution and energy crisis,new energy vehicle technology has emerged.Hybrid vehicles have significant advantages such as good power,long driving range and low emissions.Hybrid vehicles with a power coupling system using planetary gear mechanisms have a wealth of working modes and can adapt to complex and variable working conditions;during vehicle operation,it can achieve dual decoupling of the speed and torque between the engine and the wheels.Since the dual planetary hybrid vehicle has multiple power sources coupled input,in the research of transmission system control,it is necessary to comprehensively consider the efficiency characteristics of the engine and motor and the working characteristics of the power coupling mechanism,so as to improve the economy of the whole vehicle.This paper takes a city bus with a dual planetary hybrid power coupling system as the research object,starting from the analysis of the system configuration,the modeling and analysis of the main components of the power system,the establishment of the vehicle model and the power distribution control strategy to the joint simulation verification.(1)Introduce the configuration of the hybrid power coupling system,analyze and model the power components of the hybrid power bus power system,including the analysis of the speed and torque characteristics of the engine,the motor MG1 and the motor MG2,and establish the mathematical model of the power battery.On this basis,a forward simulation model of the vehicle is built in the AVL/CRUISE simulation platform to provide a basis for the research of vehicle power distribution control strategies.(2)The characteristic analysis and research on the configuration of the hybrid coupling system equipped with planetary gear mechanism.The dynamic and static mathematical models of the dynamic coupling mechanism are established using the lever method theory,and the mathematical relationship between the ideal torque and power distribution of the motor and the engine is obtained;and the power cycle phenomenon is analyzed based on the system transmission efficiency and the electric power ratio.On this basis,a mechanical point power distribution control strategy based on the optimal transmission efficiency is designed in MATLAB/Simulink,and a joint simulation is carried out with the vehicle model built in AVL/CRUISE.The results show that the mechanical point power distribution control strategy can ensure the high transmission efficiency of the system,and the vehicle equivalent fuel consumption is 21.54L/100 km.(3)In view of the problem that the engine operating points are distributed in the lowefficiency area in the mechanical point power distribution control strategy based on the optimal transmission efficiency,a fuzzy controller is designed to optimize the engine operating points.When the vehicle is running in the hybrid drive mode,the accelerator pedal opening and the power battery SOC are input,and the output demand power of the engine is the output,and a fuzzy controller is designed.Co-simulation results show that the operating point of the engine based on fuzzy optimization control has been effectively improved,the vehicle equivalent fuel consumption is 19.768L/100 km,and the economy has increased by8.23%.(4)An intelligent algorithm is introduced to further optimize the fuzzy controller.A particle swarm optimization algorithm based on simulated annealing is used to optimize the membership function and fuzzy control rules of the fuzzy controller with the least fuel consumption of the whole vehicle as the optimization function.The optimization results show that,compared with the mechanical point control strategy,the economy of the vehicle has increased by 13.85%.(5)Perform hardware-in-the-loop verification of the vehicle power distribution control strategy.Build a hardware-in-the-loop test system to complete the hardware-in-the-loop test of the power distribution control strategy in this article under CCBC cycle conditions.The results show the feasibility and effectiveness of the power allocation control strategy proposed in this paper.