What is a Moving Magnet Voice Coil Actuator?

A moving magnet voice coil actuator is a linear single phase actuator that consists of a magnet assembly attached to the load and a coil assembly connected to the static world. Moving Magnet Voice Coil Actuators are targeted as low cost pneumatic cylinder replacements. Moreover, the technology offers Moving Coil Voice Coil Actuator (MCVCA) comparable functionality and force levels. However, the moving magnet voice coil actuator (MMVCA) excels over MCVCA’s with respect to durability, efficiency and achievable stroke length. This is due to the fact that the coil is in the static part. Therefore there are no moving wires, which increases durability. Moreover it creates a better thermal path end makes it possible to apply active (water) cooling which allows for much higher force density.

In addition, the moving magnet technology lacks any mechanical gear or other reduction. It transfers force to the magnet assembly only by means of the magnetic field generated by the coil assembly. Therefore, the MMVCA accomplishes zero mechanical wear, backlash or mechanical friction and potential particle generation.

Advantages of a Moving Magnet Voice Coil Actuator

In general, the technology utilizes only a single electrical phase to control the force and position of the magnet assembly. Therefore, it is not needed to utilize a position measurement system for controlling and driving the current. As a result, driving a moving magnet actuator is similar to driving a linear BLDC motor. Therefore, the MMVCA reduces system cost, improves robustness and reduces control complexity.

•   Cost optimized solution
•   Robust
•   Ease of use