Research On Control Strategy Of PHEV

Resource scarcity and environmental pollution has become one of the most serious global problems. Energy conservation and emissions reduction are important problems which need be solved in automobile industry. All countries and the related organizations are committing to the research and development of new energy vehicles. Electric vehicles are the ultimate goal of new energy vehicles development because of zero emissions. But electric vehicles must take a long way before hitting the target in this industry considering the key engineering aspects like mileage limitation, charging difficulty and exorbitant price.It is the best choice to convert the traditional fuel cars to electric vehicles as the hybrid vehicle technology is relatively mature. Plug-in hybrid vehicle (PHEV) is closer to electric car which can be charged from the special grid or household electricity. The economic and emission performance of a PHEV is better than the traditional hybrid car. It is the research hotspot in the field of new energy vehicle. Control strategy of PHEV is the core technology of the drive train system. This will be related to the vehicle’s economy and emission performance. Therefore it is so meaningful to optimize control strategy of PHEV during the research.This article is based on the numerical simulation software MATLAB and ADVISOR. Firstly, the parameter values of the power system components are determined to meet the design requirements according to the basic parameters and performance requirements of the PHEV. Then the PHEV model is redeveloped in ADVISOR based on the parallel hybrid electric vehicle drive system structure. The matching component models and related data files are added to the new drive system model for PHEV in ADVISOR.On account of PHEV energy management problems, two kinds of practical and feasible logic threshold control strategies are established respectively named "economic model" and "hybrid model" to realize short-distance travel demand and long-distance travel demand. The overall efficiency of the engine is still one of the most important factors affecting economy and emissions of the PHEV. Considering of the engine efficiency, a kind of intelligent charging control strategy is established to improve the efficiency of the engine by improving load rate of low working point and ensuring generator to work in high efficient area.Threshold parameters of logic threshold control strategy can influence the vehicle fuel economy and emission directly. In this paper, the optimal solution of logic threshold is obtained by using genetic algorithm and then the goal of energy conservation and emissions reduction is achieved.At last, the control strategies and optimization results are summarized. Then the follow-up research work is prospected in the end.