Comparative Finite Element Analysis of a Voice Coil Actuator and a Hybrid Reluctance Actuator

抄録

This paper evaluates the performance of a hybrid reluctance actuator for application in high-precision motion systems. For this purpose, its properties are compared with those of a voice coil actuator, which is the choice actuator for many high-precision applications. To properly investigate the non-linearities of these systems, finite element analysis (FEA) is employed. Spacial-domain analysis shows that the hybrid reluctance actuator can deliver both higher forces per volume (by a factor up to app. 10.5) and thrust constant (by a factor up to app. 9.6) than the voice coil actuator. However, these values depend strongly on the position of the mover, causing a high non-linear stiffness. Frequency-domain analysis yields the power losses of the actuators, as well as the dynamic thrust constant. It is shown that at all frequencies the hybrid reluctance actuator suffers from higher iron loss (by a factor up to app. 5.1) than the voice coil actuator. Additionally, its thrust constant shows a large magnitude slope (app. -14.4dB/dec) and phase lag (app. -71^° at f=10kHz) in the frequency domain, resulting in a narrowed control bandwidth. These results clearly indicate a trade-off between thrust constant, linearity and dynamic behavior, which should be considered for employment in high-precision applications.