A comparison of the power electronic drive requirements for high bandwidth piezoelectric and electro-magnetic linear actuators

When designing high-bandwidth embedded linear actuation systems, engineers often face the choice between using a piezo-electric or electro-magnetic actuator. Often, actuator performance characteristics such as energy density, stiffness, frequency response and loss are used to specify the system configuration, whilst the power electronic drive requirement is overlooked. This paper demonstrates the challenges involved in developing an amplifier for a high-voltage piezo-electric actuator. An amplifier designed to drive an electro-magnetic actuator with comparable output capability to the piezo-electric actuator is also presented; this amplifier is significantly smaller and lighter and has higher output signal quality. This suggests that in terms of overall system performance, the power electronic drive requirements of candidate actuators should not be overlooked.