Installation manual

System Operation 08/04 Danaher Motion Kollmorgen
70 M-SS-001-01 Rev. T SERVOSTAR S Installation
7.3.3.2. Analog Torque
The SERVOSTAR can be often configured to operate as an analog
torque loop controller (OPMODE 3). In this case, the current loop
receives its input from the analog-to-digital (A/D) conversion
system. After conversion, the input command signal is processed
through an algorithm that adjusts the signal (ANOFF, ANDB,
ANZERO), filters it (ANLPFHZ) and then scales it (ISCALE), before
developing the current command (ICMD). The current (or torque)
command is then checked against peak (IMAX, ILIM) and
continuous (FoldBack features, ICONT) current clamp limits.
Sinusoidal commutation modulation is added to the command and
then fed to the three-phase current loop regulator, which calculates
a current error. This error is then fed through a digital pole-
placement compensation algorithm. The output of the compensator
is converted to a PWM signal and fed to the power transistor
bridge. The actual motor current is updated and the process begins
again.