Installation manual

Danaher Motion Kollmorgen System Operation
SERVOSTAR
®
S and SERVOSTAR
®
CD Series 73
Torque Loop Operation
The design of the control loops was discussed in the previous section. Now, the
operation as a system is presented. The SERVOSTAR has many internal
variables that are used to examine and dictate system operation. Many of these
variables and their locations in MOTIONLINK are presented graphically in the
following discussions to help disclose meanings and relationships.
SERIAL TORQUE
The SERVOSTAR can be operated as a serial torque-controlled amplifier
(OPMODE 2). It receives a serial command (T) via a host to a command
generator, which in turn creates a current command (ICMD). The current (or
torque) command is 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 power
bridge uses the high voltage DC BUS Module (typical 325 VDC bus) to supply
the required current to the motor windings. The actual motor current is updated
and the process begins again. The following graphic is a representation of the
serial torque loop operation (refer to the VarCom Reference Guide for details on
all variables and commands).