Positionerprecorrectorexcitationsignalset - Newport XPS Programmer's Manual

XPS Unified
7.2.1.282

PositionerPreCorrectorExcitationSignalSet

Name
PositionerPreCorrectorExcitationSignalSet – Configures and activate the signal of
pre-corrector excitation.
Input tests
- Refer to section 7.1: "Input Tests Common to all XPS Functions".
- Valids object type: (-8)
- Is secondary positioner or has a secondary positioner: (-8)
- Checks frequency (must ≥0.1 and ≤0.5/CorrectorISRPeriod): (-17)
- Checks amplitude (must >0): (-17)
- Checks excitation time (must ≥4 * CorrectorISRPeriod): (-17)
- Valids positioner name: (-18)
- Checks group status (must be READY): (-22)
- Valids control loop type: (-24)
- Checks position (CurrSetpointPos ≤UserMaximumTargetPosition and
CurrSetpointPos-2Amplitude ≥UserMinimumTargetPosition): (-35)
- Checks maximum velocity (Amplitude * ω <MaximumVelocity): (-68)
- Checks maximum acceleration (Amplitude * ω² <MaximumAcceleration): (-69)
Description
The pre-corrector excitation signal functionality generates sine-wave signals
(ExcitationPosition, ExcitationVelocity, ExcitationAcceleration, ExcitationJerk)
inserted in the position control loop (in closed or open loop configuration) to excite the
system. In measuring the output signal (eg. encoder position, velocity or acceleration)
of the excited system, we can determine some system characteristics, like the system
transfer function.
The exact forms of generated pre-corrector excitation signals are as follows:
ω = 2πF (F: excitation frequency)
ExcitationPosition = A * cos(ωt) – A (A: excitation amplitude, t: current time)
ExcitationVelocity = (-Aω) * sin(ωt)
ExcitationAcceleration = (-Aω²) * cos(ωt)
ExcitationJerk = (Aω
The pre-corrector excitation signal functionality is only available with the stages
controlled in acceleration (acceleration control, ex: brushless / linear motors), velocity
(velocity control) or in voltage (voltage control). It does not exist with stages controlled
in position (ex: stepper motors).
The excitation signal function PositionerPreCorrectorExcitationSignalSet can be
executed only when the positioner is in "READY" state. When the excitation-signal
process is in progression, the positioner is in the "ExcitationSignal" state. At the end of
the process, the positioner returns to the "READY" state (see group state diagram).
The PositionerPreCorrectorExcitationSignalSet function sends a sine form excitation
signal to entry of position control loop during a time. This function is allowed for
"PIDFFAcceleration", "PIDFFVelocity" or "PIDDualFFVoltage" control loops. The
parameters to configure include: frequency (Hz, double), amplitude (position unit,
double) and during time (seconds, double).
3 ) * sin(ωt)
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Programmer's Manual
EDH0373En1023 — 01/18