Galil is introducing a new single axis linear drive package: the DMC-3x014.  The new DMC-3x014 contains a 20W linear brushless servo drive with sinusoidal commutation.  The transconductance linear amplifier has an operating gain of 0.2 A/V, with a current loop bandwidth of 4 kHz.  The amplifier can drive brushless motors operating at up to 1 Amp continuous, and 2 Amp peak at 15-40 VDC. 

Trapezoidal commutation can have discontinuities and produce a torque ripple.  This is because the torque characteristics of the motor are only taken into account in six zones.  With sinusoidal commutation, the torque characteristics of the motor are mapped to all positions, resulting in continuous commutation with no torque ripple.  As an additional benefit of sinusoidal commutation, Hall sensors are generally not required with Galil’s initialization commands.

As the DMC-3x014 uses a linear servo amplifier, it applies the full commanded voltage across the power transistors.  There is no switching of the power as seen in PWM amplifiers.  This minimizes electrical noise and the effects of motor inductance on the current ripple.  This makes the DMC-3x014 ideal for using low inductance brushless motors in low power applications. 

The DMC-3x014 is available as an option for Galil’s DMC-30000 series of single axis controller/drive packages.  The standard DMC-3x014 will use a 12 bit DAC, however there is a 16 bit option to increase the current resolution for systems with high feedback gain.  A ‘–BRUSH’ option is also available, enabling the use of brush type motors.  Designed to minimize space, cost and wiring, the drive reside directly inside the controller enclosure for a compact profile at a size of 3.88” x 5.00”.  The U.S. list price of the DMC-3x014 is $695 in single quantity and $445 in 100 quantities.