Simulation Research of the Fuzzy Torque Control for Hybrid Electrical Vehicle Based on ADVISOR Bo-jun Zhang, Yu Wang, Jia-tian Guo Department of Automotive and Transportation, Tianjin University of Technology and Education, Tianjin, China (zhangbojun808@126.com) Abstract - The simulation model of the super-mild hybrid electrical vehicle is established through the simulation software ADVISOR. The fuzzy logic torque distribution controller of motor and engine is designed. The drive cycle selects Urban Dynamometer Driving Schedule(UDDS). The simulation results show that the fuzzy torque controller of motor and engine can properly distribute the torque. The fuel economy and emission performance are improved. Key words - ADVISOR, hybrid electrical vehicle, simulation, torque control I. VEHICLE SIMULATION MODEL The simulation model of the super-mild hybrid vehicle is established through the simulation software ADVISOR. This Model is shown in Fig. 1. The backward simulation and forward simulation can be used in ADVISOR. The backward simulation can Fig. 1. calculate the engine and motor output power. Forward simulation is to be after the backward simulation, it can use the engine and motor power along with backward simulation passing in the opposite direction. The actual speed of vehicle is calculated by the forward simulation [1] . Every module in the vehicle simulation model contains a simulink simulation module. We can modify the parameters in the M-file for data input [2]. The parameters in the M-file of vehicle module are modified according to the parameters of the entire vehicle, such as: veh_gravity=9.81; % m/s^2 veh_air_density=1.2; % kg/m^3 veh_mass = 865; % (kg) vehicle_height = 1.380; % (m) vehicle_width = 1.590; % (m) veh_CD=0.38; veh_FA=1.7; % (m^2) veh_wheelbase=2.365; % (m) The super-mild hybrid vehicle simulation model II. TORQUE FUZZY LOGIC CONTROL The super-mild hybrid electrical vehicle has no pure electric operating mode. Motor only be used for idle starting, stopping, power compensation and recycling braking energy, so the motor torque control will affect the vehicle performance [3-6]. The output torque of the engine can be divided into two parts:One is used to drive the vehicle, the other is used to drive the generator for the battery charging. The input/output torque of the motor can balance the relationship between engine torque and vehicle required torque, which controls the engine working point along the economic curve [7] [8]. When the engine output torque is lower than the vehicle required torque, the motor will make up the difference. When the engine output torque is higher than the vehicle required torque or the vehicle is in deceleration braking condition, the extra engine output torque or the recovery of deceleration energy can drive generator for battery charging [9-13]. The fuzzy controller not only improves the vehicle fuel economy but also makes the battery SOC value to be in the high efficiency range. Take the differential values between the vehicle required torque and the engine output torque (Tc), and battery SOC values to be input variables. Take the torque adjustment parameter to be output variables. The membership function is shown in Fig. 2. Fig. 4. Torque control III. SIMULATION RESULT The simulation results are shown in Fig. 5. Fig. 2. Membership function Input and output variables of the fuzzy sets are as follows: The fuzzy set for the SOC is: {L, PL, W, PH, H}. The fuzzy set for the Tc is:{FD, FX, W, ZX, ZD}. The fuzzy set for the V is: {X, PX, W, PD, D}. Fig.5 Simulation results Where: L represents low, PL represents partial low, W represents moderate, PH represents partial high, H The engine fuel economy and emission values are represents high, FD represents negative bigness, FX shown in Table I. represents negative smallness, ZX represents positive TABLE I smallness, ZD represents positive bigness, X represents ENGINE FUEL ECONOMY AND EMISSIONS smallness, PX represents partial smallness, PD represents fuel partial bigness, D represents bigness. Emissions(grams/mile) Torque economy( 25 fuzzy control rules are designed to describe the controller L/100km) HC CO NOX relationship between input and output. There are some rules to illustrate its function, IF is the premise and THEN is the Without conclusion: fuzzy 0.47 0.422 10.82 0.113 controlier a. IF(Tc is W) THEN (k is W) b. IF(SOC is L)and(Tc is FX) THEN (k is W) With c. IF(SOC is PL)and(Tc is FD) THEN (k is X) fuzzy 0.35 0.33 6.456 0.113 d. IF(SOC is H)and(Tc is ZX) THEN (k is X) controller e. IF(SOC is PH)and(Tc is ZD) THEN (k is PD) … The simulation results show that the battery SOC value The modules of < cl > and <tc> realize the fuzzy logiccan be maintained in the high efficiency range. And the fuel torque control, as shown in Fig.3 and Fig. 4. economy of the engine has been improved, the HC and CO emissions have been lower. IV. CONCLUSION Fig.3 Clutch control The ADVISOR simulation model and the fuzzy logic torque controller are established. The fuzzy logic torque controller is realized through the clutch and torque control module. The fuzzy torque control strategy can more effectivly distribute the motor and the engine operating range. The fuel economy of the vehicle has been improved and the emissions have been lower. ACKNOWLEDGMENT This dissertation is under the project support of Natural Science Foundation of Tianjin (09JCYBJC04800). REFERENCES [1] Wipke K B, Cuddy M R, Burch S D. 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