Pacific Scientific OC930, Справочное руководство по аппаратному и программному обеспечению

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Command
processing
The analog input goes through a number of signal processing
steps before becoming the actual motor velocity command
VelCmdA
as shown by Figure 1 in Appendix C.
1. Analog input differential amplifier with 1200 Hz low pass
filter.
2. High resolution A/D sampled at the velocity loop update rate
and added to the ADOffset parameter.
3. ADF0 adjustable low pass filter to become the AnalogIn
variable.
4. Range clamped by the
VelLmtHi, VelLmtLo
parameters.
5. d/dt slew limit clamped by the
AccelLmt, DecelLmt
parameters to become the
VelCmdA
variable.
Velocity loop
compensation
The actual velocity command (
VelCmdA
) is then combined with
the measured shaft velocity (
VelFB
) and processed by the
velocity loop compensation to create the motor torque current
command (
ICmd
). The detailed signal processing steps to create
ICmd are listed below and shown in Figure 2 in Appendix C.
1.
VelErr
set equal to (
VelCmdA - VelFB
)
2. The anti-resonance second order velocity loop compensation
block controlled by the ARF0, ARF1, ARZ0, and ARZ1
parameters to become the
FVelErr
variable.
3. The proportional and integral velocity loop compensation
block controlled by the
KVP
and
KVI
parameters
respectively.
4. And finally through the
IlmtPlus
and
IlmtMinus
current
command clamp to become the
ICmd
motor torque current
command variable.
Although this looks like a lot of parameters to set, the automated
set up capability of 930 Dialogue usually sets all of them
properly. The only parameters that typically need user
adjustment are the desired block gain (
CmdGain
) and the
velocity loop tuning gain ( KVP ). For more information on tuning
the velocity loop see Chapter 6 Servo Loop Parameters.
MA930 Manual 4 - 5