Research Of System Control Technology For Full Hybrid Vehicle

Having the merits of traditional fuel vehicle and pure electric vehicle, hybrid car is the idealchoice for recent vehicle development. The full hybrid vehicle, being popular among vehiclemanufacturers, has become the major trend of future hybrid vehicles because of its great fuelefficiency, good energy saving effect, and high market share. Based on the research and analysis ofthe structure and working principles of full hybrid vehicle power system, and the comparison withadvanced hybrid technology, this paper designed the vehicle operating mode, state control method andits matching system control algorithms. With the help of modeling and rapid control prototypingtechnology, the correctness of the system control algorithms was verified successfully through controlsystem simulation, powertrain bench test and revolving drum test. This paper could provide technicalguidance and reference for the research and development of the same type of hybrid vehicles.The paper designed and researched the structure, working principles and the car operating modeof full hybrid vehicle power system in comparison with the structure and advantages/disadvantages ofclassical and advanced hybrid technology. Using torque control method and power balance controltechnology, the shaft torque equations, torque balance equation, kinetic equation and the vehicleelectric power balance equation, kinetic equation of the double planetary line of full hybrid vehiclepower system were obtained with mathematical analysis. And the basic function of power system wasdevised for calculating power components torque and power on the basis of above mentionedmathematical equations.Based on basic equations and equivalent lever principle of power system, the system controlalgorithm of vehicle operating mode and state control was designed through the analysis andcalculation of different running modes of full hybrid vehicle and the controlled study of the status offull hybrid vehicle key components, such as the status of vehicle gear, the engine and the brake, aswell as the computation and defining of the key parameters, such as the motor capacity, the enginecapacity, the power battery capacity, the vehicle demand torque, the power battery charge statethreshold and the engine water temperature threshold.The system control models of the power system basic equations, operation mode controlalgorithms, the key components’ status control algorithms and the calculating and defining algorithmsof key parameters were built with Simulink/Stateflow modeling software. Using MotoTron rapidcontrol prototyping system development tool, these system control models were integrated into rapidcontrol prototyping system, based on which the correctness of the system control algorithms wasverified successfully through system simulation, powertrain bench test and revolving drum test from two aspects of static and dynamic test.The vehicle system control algorithm of the full hybrid vehicle in this paper was developedutilizing torque control method and power balance control technology. With the reasonabledistribution of engine energy, it had reduced the fuel consumption and emissions, ensuring the stableoperation of the vehicle as well as the smooth switching between different running modes. As a result,the vehicle realizes the optimal control object in terms of economy, power and emission performance.Referring to the research findings of hybrid vehicle system control algorithm, this paper studiedand researched the advanced hybrid vehicle power system structures and system control algorithmrepresented by Prius, Insight and Volt, analyzed and compared the shortcomings of hybrid vehicletechnology development in China, and affirmed the planetary line power split system as the maintrend of hybrid vehicle power system structure. It could be a necessary technical assist to China’s owndevelopment and design of hybrid vehicles, and fill the blank of research and experiment of powersplit full hybrid vehicle system control technology, and could be profound significance for futuredevelopment of China’s automobile industry.