Research and Development of an Electromagnetic Actuated Active Suspension

Active suspension could achieve good ride comfort and road holding performance. Traditional active suspension which utilizes air actuator or hydraulic actuator features relatively slow response or high energy consumption. Utilizing Permanent Magnet Synchronous Motor (PMSM) as actuator, the Electromagnetic Actuated Active Suspension (EAAS) benefits quick response and energy harvesting from vibration at the same time. Benchmarked with luxury cars available on the market, design parameters and design boundary are determined. A mechanism includes push bar and bell crank is designed to transfer the rotary motion of PMSM into linear motion of suspension, or verse vice. A prototype of EAAS is built in compromise of limited budget and a test bench is designed and set up. Different from conventional quarter car model, the model of EAAS in this paper is investigated and the total inertial of PMSM, gearbox and suspension control arms are calculated and simplified as an equivalent mass. Also, variation of system parameters caused by characteristics of suspension K&C are investigated and modeled as uncertainty. Basing on this quarter car model, two μ synthesis controllers are developed to achieve good ride comfort and good stability respectively. Test results show that good ride comfort could be achieved with minor energy consumption and good stability could be achieved with energy harvesting at the same time.