An Optimal Algorithm for Energy Recovery of Hydraulic Electromagnetic Energy-Regenerative Shock Absorber

This paper presents a new kind of shock absorber, hydraulic electromagnetic energy-regenerative shock absorber (HESA), which can recover energy from vibration of vehicles. The road excitation frequency, load resistance and damping ratio are found to greatly affect the energy recovery of HESA. Based on a quarter-car model, the optimal load resistance and damping ratio for maximizing the energy-recyclable power are discussed. The results indicate that for any excitation frequency, the energy-recyclable power first increases then decreases with the load resistance increase, and the optimal load resistance is changeable as the excitation frequency changes. Moreover, the energy-recyclable power is more sensitive to excitation frequency than to damping ratio, and the ideal excitation frequency for energy recovery is around the wheel resonant frequency. The exploration of active control of HESA confirms that the damping force varies with the load current magnitude, and the active control can be realized by appropriate matching.