Model Predictive Control For A Plug-in Hybrid Electric Vehicle Based On Majorized SOC Trajectory

The large-capacity battery equipped on Plug-in Hybrid Electric vehicle(PHEV) canbe charged from the ordinary grid，and more electrical energy can be used during thevehicle driving, which reduce the fuel consumption and exhaust emission. The energymanagement strategy of PHEV differs from the conditional hybrid electric vehicles, so asuitable control strategy for PHEV should be raised to make full use of the theadvantage of saving fuel and reducing exhaust emission. The main contents are asfollows:①The mathematical modes of power component are built, obtaining the fuelmathematical mode of engine, efficiency mode of motor and calculating mode ofbattery.②The fuel economy global optimization mode of PHEV is created by DynamicProgramming, which select the minimum equivalent fuel of the entire cycle asobjective, and fuel economy simulation of PHEV is accomplished in NEDC, UDDSand Japan1015cycle of50km,100km and150km, and got the conclusion that the“depleting mode” is the most suitable control strategy for PHEV. The driving cycle isdivided into general condition, transition condition and special condition by thecharacteristics of the cycle, and three different SOC change styles of the cycles from theglobal results are as follows: The SOC in general condition varies along the straight linethrough the SOC point at the beginning of the general condition and the SOC point atthe end of the cycle simultaneously.③A method of tracking the SOC of the global optimization was proposed, thecondition type of the forecast horizon can be determined from the future period ofconditions(Detection Sight);The target SOC at the end of the forecast horizon wereacquired according to different condition styles of the forecast horizon. At last the fueleconomic predictive control mode based on dynamic programming of PHEV wasestablished.④The program of the fuel economic predictive control mode of PEHV waswritten in C language, which was simulated along with MATLAB/Simulink inS-function written by external program interface. The SOC could match the optimalSOC trajectory of global optimization well in NEDC、UDDS and Japan1015drivingcycles, and the operating point of the engine and motor located at the efficient district, which demonstrate the validity of the proposed mode predictive control method. basedon optimal SOC trajectory, and the real-time operation feasibility was verified bydSPACE, indicating that the mode predictive control algorism meet the acquirementof real time control.