Power Drivers for MR Dampers

This chapter discusses some aspects of power drivers for MR dampers based on pulse-width modulation (PWM) amplifiers. These digital devices are inexpensive to make when using modern module-based switching circuitry, offer significant benefits in terms of lower power consumption and have been widely used within the automotive industry. The authors provide PWM fundamental principles, and then discuss current responses in the electrical circuit of an MR damper subjected to PWM type inputs. The theory is followed by experimental investigation of an automotive MR damper driven by a PWM power driver in open loop and closed-loop configurations.