Study On Matching And Control Strategy For Super-mild Hybrid Transmission System

Super-mild hybrid electric vehicle is based on the new reflux stepless automatictransmission system, it has a large range of speed ratio, and low-power motors can be used as anauxiliary power source for a new car. it not only has a characteristic idle start-stop, recyclingregenerative braking, but also achieving ultra-low speed climbing and reversing incircumstances of pure electric drive. Due to using low-power motor, the number of relevantbattery pack is small, and small in size. So Super-mild hybrid electric vehicleis has better fueleconomy and emission performance.The topic based on the new reflux stepless automatic transmission system，making suredrive system parameter matching, develop the vehicle simulation model, Made the controlstrategy in some specific conditions, obtaining the corresponding results by simulation. Andspeed ratio control, low power loss in certain conditions test verification carried out by using theexisting test equipment.Analyze the advantages and disadvantages of all kinds of Hybrid layout form, Aftercomprehensive consideration, ensure super-mild hybrid electric vehicle transmission systemlayout form. Setting the transmission system main working mode, preliminary analisisuper-mild hybrid electric vehicle feature. To select engine, motor and battery, determines themaximum efficiency working curve of the engine and motor.Making the control strategy of vehicle, using Matlab/Simulink establish vehicle simulationmodel. Illustrate some special structure module thoughts and concrete control methods, It givesfull preparation to the next simulation.The simulation analysis was carried out on the normal running condition. To establish theidentification rules of working condition transformation. Emulation proof for theconversion,include of low gear to high gear, high gear to low gear, respectively. The wholevehicle performance simulation analysis was carried out on the super-mild hybrid electric vehicle,To obtain the specific parameter of power performance and fuel economy.Ultimate, based on the hardware-in-the-loop test bed, research of speed ratio control andpower loss for the super-mild hybrid electric vehicle in high gear case. The speed ratio controlresults show coupling speed‐ratio control is better；the power loss results confirm that somespecific rules of no-load power consumption.