Research on the torsional vibration performance of a CVT powertrain with a dual-mass flywheel damper system

Abstract

Continuously variable transmissions (CVTs) can achieve continuous changes in speed ratio and can better improve the ride comfort of the car. However, the torque fluctuation of the engine will reduce its transmission efficiency, and the torsional damper is usually matched to improve transmission efficiency and reduce vibration noise. In this paper, the model of a complete vehicle power transmission system was established by using the bond graph method. The relationships between each state variable were obtained according to the system causality and the direction of the power flow, based on which the dynamic model of the entire vehicle power transmission system was derived. A simulation of the powertrain with dual-mass flywheel-continuously variable transmission (DMF-CVT) was carried out, and the torsional stiffness of the dual-mass flywheel (DMF) was optimized. Taking a certain sport-utility vehicle (SUV) as the test bench, the vehicle road testing of the DMF before and after improvement was carried out, and the test results before and after the improvement were compared to verify the correctness of the optimization direction, which provided a reference for the matching and optimization design of the DMF-CVT power transmission system.

Parameter Optimization and Control Strategy of Hybrid Electric Vehicle Transmission System based on Improved GA Algorithm

“…The vibration and noise in the running process are reduced, and the driving comfort is improved through the optimization method of vehicle state variables. Simulation experiments show that the method verifies the effective performance of the optimized parameters and provides a reference for DMF simulation [10]. Rajan et al took HEV as the research object and designed the optimized hybrid transmission to control the cost of the vehicle.…”

“…Formula (10) is a specific calculation. (10) CF 1 indicates that the power of the hybrid vehicle is greater than or equal to the design requirements in Formula (10). CF 2 indicates that the power of the hybrid vehicle at the maximum speed is greater than the design requirements.…”

Optimization of Radio Energy Transmission System Efficiency Based on Genetic Algorithm

“…Due to the resonance frequency being equal to that of the receiving coil, the circuit in the transmitting coil generates resonance, and its current generates an electromagnetic field of the same frequency that is coupled to the receiving coil by the near field. It is then supplied to the load through a rectification circuit to achieve wireless energy transmission [10,18]. According to the equivalent circuit and KVL law, the circuit equation is listed as follows (3.1):…”