Control of semi-active inertial suspension system for hub motor driven vehicles

Reducing vibrations for the hub motor driven vehicle (HMDV) under the adverse effects of the unbalanced radial force of the switched reluctance motor (SRM) and road surface excitation is essential to enhance the overall performance of electric vehicles. To address this issue, a quarter dynamic model of the HMDV is established. Subsequently, four structures of the inertial suspension system are proposed to improve vibration isolation for the HMDV. To achieve this, the Particle Swarm Optimization (PSO) algorithm is employed to optimize the parameters of the inertial suspension system. The root mean square (RMS) values of body acceleration, suspension working space, and dynamic tire load are chosen as the objective functions. Finally, two representative structures of the inertial suspension system are selected and developed into semi-active inertial suspension systems to further enhance vibration isolation performance for the HMDV. Fuzzy logic control (FLC) is then applied to control the damping coefficient of the semi-active inertial suspension system. To improve the effectiveness of the FLC, the PSO algorithm is used to optimize the input and output ranges of the FLC. The performance of the semi-active inertial suspension system is thoroughly evaluated in both the time and frequency domains. The results show that the semi-active inertial suspension system significantly improves ride comfort, driving safety, and road friendliness compared to the conventional suspension system. These findings underscore the potential of semi-active inertial suspension systems to significantly enhance vibration isolation for the HMDV.