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With increasing pressure from environment problem for reduction in CO2 emissions and stricter fuel targets from road vehicles, new transmission technologies are gaining more attention in different main market. To get suitable road load data for transmission durability development is becoming increasingly important and can shorten the development time of new transmission. This paper presents the procedure and methods of road load data development for durability design of transmission product and optimization based on the real road data measurement, statistical characteristics evaluation and fatigue damage equivalency. Apply this road load data method procedure on 3 type of vehicle which represent conventional vehicle, BEV and HEV.

With increasing pressure for reduction in CO2 emissions and stricter fuel targets from road vehicles, OEMs around the globe have to electrify their vehicle range to meet increasingly challenging emission standards in recent years and new transmission technologies are gaining more attention in different main markets. The actual and future powertrain development has three major directions in order to reduce or avoid emissions in the transportation sector: Hybrid Vehicles: Hybrid Electric Vehicles (HEV), Plug-in HEV (PHEV) Electric Vehicles (EV); Range Extender Electric Vehicle (REEV); Fuel Cell Electric Vehicles (FCEV), Range Extender FCEV (REFCEV). This paper presents a new type Hybrid transmission which is called “DHT (Dedicated Hybrid Transmission)” technology for cost-effective HEVs and PHEVs; it permits the design of very compact automatic transmissions with an integrated high-voltage electric motor on the output side of the transmission.

Tire cavity noise of pure electric vehicles is particularly prominent due to the absence of engine noise, which are usually eliminated by adding Helmholtz resonators with arbitrary transversal section to the wheel rims. This paper provides theoretical basis for accurately predicting and effectively improving acoustic performance of wheel resonators. A hybrid finite element method is developed to extract the transversal wavenumbers and eigenvectors, and the mode-matching scheme is employed to determine the transmission loss of the Helmholtz resonator. Based on the accuracy validation of this method, the matching design of the wheel resonators and the optimization method of tire cavity noise are studied. The identification method of the tire cavity resonance frequency is developed through the acoustic modal test. A scientific transmission loss target curve and fitness function are defined according to the noise characteristics.

The backlash between engaging components in a driveline is unavoidable, especially when the gear runs freely and collides with the backlash, the impact torque generated increases the vibration amplitude. The power-split hybrid electric vehicle generates output torque only from the traction motor during the launching process. The nonlinear backlash can greatly influence the driveability of the driveline due to the rapid response of the traction motor and the lack of the traditional clutches and torsional shock absorbers in the powertrain. This paper focuses on the launch vibration of the power-split hybrid electric vehicle, establishes a nonlinear driveline model considering gear backlash, including an engine, two motors, a Ravigneaux planetary gear set, a reducer, a differential, a backlash assembly, half shafts, and wheels.