PWM Design for Active Suspension without External Energy Supply Based on LQG Control

A PWM controller is designed for the active suspension without external energy supply (ASWEES) using the LQG control method. Based on the quarter-vehicle ASWEES model, Energy flow equation between the suspension and the accumulator with a 2 kW load was deduced and a PWM controller was designed. When 200Hz solenoid valves were adopted, the carrier frequency and series value of the carrier signal were set as 40 and 5 respectively. Simulation results show the suspension quadratic performance index of ASWEES decreases 24.97% than that of the passive suspension. The passive suspension consumes 2.211kW power, but ASWEES reclaims energy of 2 kW.