Reduction of the number of power amplifiers for an advanced single-stage planar actuator

Moving-magnet planar actuators typically have many stator coils, of which the current is controlled individually. Only the coils that lie directly underneath the translator have to be powered. Hence a large reduction in the number of power amplifiers is possible, thereby reducing system complexity and cost as well. A multiplexer topology based on solid-state switches is proposed to be able to use a minimal amount of amplifiers. Active leakage current reduction circuitry is proposed to prevent amplifier performance degradation by the multiplexer. A high common mode rejection current transformer is designed and built for the measurement of the induced noise current.