244 / 2021-04-14 16:58:23

Fractional order control of nonlinear active suspension with input delay

Fractional order; nonlinear; active suspension; input delay

The common linear representation tends not to describe the spring and damping of a realistic vehicle suspension. In order to establish a mathematical model of active suspension closer to the true one, cube item and fractional order are introduced to depict the spring and damping respectively. Two independent fractional order controllers are designed to improve the ride comfort of the suspension. Vertical acceleration of car body and dynamic deflection of the suspension are selected as the two controllers'  feedback variables respectively and the sum of the controllers' outputs is directly as the active input of the suspension. The parameters of the two controllers are tuned by using the quantum particle swarm optimization (QPSO).Compared with the integer order controller, the simulation results show that the active suspension with double fractional order control has better vibration reduction performance.