High-precision and high-speed positioning of 100 G linear synchronous motor

• The improved prototype moving permanent magnet linear synchronous motor (MPM LSM) provides motion at an acceleration above 100 G and a velocity above 12 m/s.
• The control system with the MPM LSM shows a positioning accuracy and a positioning resolution of 500 nm, which is similar to the vibration amplitude of the sensor output in open loop.
• Continuous positioning for longer than 30 minutes increases the temperature of the MPM LSM, but by less than 6 °C.

The present paper describes a moving permanent magnet linear synchronous motor (MPM LSM) that can move with an acceleration above 100 G (=980 m/s2), and is also capable of high-precision and high-speed positioning. The MPM LSM consists of a mover including permanent magnets and a double-sided electromagnet stator. It can produce a thrust of 4.56 × 103 N and has a working range wider than 1 m. The MPM LSM mover is improved for light weight and is driven using a suitable phase lead for flux weakening. The combination of the improved mover and the suitable phase lead provides motion at an acceleration above 100 G and a velocity above 12 m/s. The positioning characteristics of the improved MPM LSM are examined using a controller with two suitable phase lead functions. The control system shows a positioning accuracy and a positioning resolution of 500 nm, which is similar to the vibration amplitude of the sensor output in open loop. In 300-mm step positioning, the improved MPM LSM shows an acceleration above 660 m/s2 and a velocity above 8.3 m/s. It takes less than 101 ms to reduce the positioning error to less than 5 μm. The temperature rise during positioning is also examined experimentally. Continuous positioning for longer than 30 minutes increases the temperature of the MPM LSM, but by less than 6 °C.