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The vibration characteristics of hybrid vehicles are very different from that of traditional fuel vehicles. In this paper, the active and passive control schemes are used to inhibit the vibration issues in vehicle hybrid powertrain system. Firstly the torsional vibration mechanical model including engine, motor and planetary gear subsystems is established. Then the transient vibration responses of typical working condition are analyzed through power control strategy. Consequently the active and passive control of torsional vibration in hybrid powertrain system is proposed. The active control of the motor and generator torque is designed and the vehicle longitudinal vibration is reduced. The vibration of the planetary gear system is ameliorated with passive control method by adding torsional vibration absorbers to power units. The vibration characteristics in vehicle hybrid powertrain system are effectively improved through the active and passive control.

Brake judder severely affects the riding comfort and safety of vehicle. For the brake corner system, a rigid-flexible coupling model is established based on ADAMS. In the model, brake pads, caliper, anchor and knuckle are flexible bodies, and the contacts between pads and disc and the contacts between pads and caliper are defined in detail. Meanwhile, the vibration acceleration of the brake corner components and the contact forces between disc and pads are used as evaluation index and the evaluation system of brake judder are improved. The analysis results show that the novel model and evaluation system can be used to predict brake judder effectively.

The transient thermo-mechanical coupling dynamic model of ventilated disc brake with asymmetrical outer and inner thickness was established by means of Msc-marc software. In the model, pad backplate is simplified as a rigid surface with the same shape of brake lining and is bonded together with brake lining. Control node is associated with the rigid surface and the equivalent force that replaces the pressure is applied on the control nodes, of which the degrees of freedom in radial and rotational directions are constrained. With distribution characteristics of disc temperature field, normal stress field and lateral thermo-elastic deformation and thickness for the evaluation, the impacts of brake pad constraints on brake thermomechanical coupling characteristics were analyzed. The simulation results show that the brake pad back plate is an important structure in brake thermo-mechanical coupling analysis, which can’t be ignored in simulation computing.

The design method for the powertrain mounting system in internal combustion engine vehicles is well-established. Electric vehicles experience higher vibration frequencies and more significant transient responses when accelerating or braking than fuel vehicles due to their high speed and fast response. Therefore, the design of the electric drive assembly mounting system requires further development. The modeling of electric drive assembly mounting systems often neglects the mounting bracket’s influence, which significantly affects the center of mass and rotational inertia of the electric drive assembly. This paper examines the effect of the mounting bracket in the electric drive assembly mounting system. It establishes a mathematical model with six degrees of freedom for the mounting system, considering the mounting bracket. By comparing the natural characteristics and the transient response, it is discussed whether the mass of the mounting bracket greatly influences the system.

It is considered that slow convergence speed and large calculation amount of commonly used adaptive algorithm in the active control system for vehicle interior noise yield noise reduction performance and hardware requirements problems. In this paper, a 4-channel active control of vehicle interior noise based on adaptive notch filter is established, and road test is carried out to test and analyze the performance of the control system. Firstly, the general mathematic model of the multi-channel active control system based on adaptive notch filter is established. The computational complexity of the algorithm is analyzed and compared with that of the FXLMS algorithm. Secondly, a hardware-in-the-loop test bench based on multi-channel adaptive notch filter is set up, to measure the noise reduction performance of ANC system under various working conditions.

Powertrain system of series-parallel hybrid vehicle contains multiple excitation sources like engine, motor and generator. The reduction of noise and vibration is quite difficult during multiplex working modes or the switch of modes. Aiming at Series-parallel hybrid powertrain system which contains engine, motor and planetary gear subsystems, this paper considered a typical working condition which is based on the power control strategy and established the torsional vibration mechanical model of hybrid powertrain system. The inherent characteristics and transient vibration response of the electric mode, hybrid mode and parking charging mode were studied and it was discovered that the repetitive frequency of the powertrain system under the three working modes is the same which is only related to inertia and meshing stiffness of planetary gear system. The non-repetitive frequency and corresponding vibration modes under the electric mode and parking charging mode are both close.