Delta Tau GEO BRICK LV 사용자 설명서
Turbo PMAC User Manual
Motor Compensation Tables and Constants
161
Ixx67: Following Error Limit
Ixx67 is a saturation limit on the magnitude of the following error input to the P and I terms of the filter.
It does not limit the true following error, or the error value compared to the Ixx11 and Ixx12 following
error limit parameters. Setting Ixx67 to 0 disables the PI control terms, while leaving the D derivative
term (i.e. the velocity loop) and the feedforward terms active. This setting is useful if only velocity
control is truly desired. If Ixx67 is set to 0, Ixx11 should also be set to 0 to make sure the motor does not
trip on a fatal following error fault.
It does not limit the true following error, or the error value compared to the Ixx11 and Ixx12 following
error limit parameters. Setting Ixx67 to 0 disables the PI control terms, while leaving the D derivative
term (i.e. the velocity loop) and the feedforward terms active. This setting is useful if only velocity
control is truly desired. If Ixx67 is set to 0, Ixx11 should also be set to 0 to make sure the motor does not
trip on a fatal following error fault.
Ixx68: Friction Feedforward
Ixx68 is a non-linear friction feedforward term. The magnitude of Ixx68, multiplied by the sign of the
instantaneous commanded velocity, is added directly to the output of the servo filter. It is meant to
compensate for dry (Coulomb) friction.
instantaneous commanded velocity, is added directly to the output of the servo filter. It is meant to
compensate for dry (Coulomb) friction.
Ixx69: Output Limit
Ixx69 is a saturation limit on the output of the servo filter. If the output value is limited by Ixx69, the
input to the position-loop integrator is turned off automatically, and the output of the integrator remains
constant in this condition.
input to the position-loop integrator is turned off automatically, and the output of the integrator remains
constant in this condition.
Ixx29, Ixx79: Offset Terms
If Turbo PMAC is not performing commutation for Motor xx, Ixx29 is a fixed offset term on the output
of the servo filter, in units of a 16-bit DAC (even if some other device is used). If Turbo PMAC is
performing commutation for the motor, Ixx29 and Ixx79 serve as phase offsets in the commutation
algorithm.
of the servo filter, in units of a 16-bit DAC (even if some other device is used). If Turbo PMAC is
performing commutation for the motor, Ixx29 and Ixx79 serve as phase offsets in the commutation
algorithm.
Extended Servo Algorithm
For systems with more difficult dynamics, such as multiple resonances and low-frequency resonances, the
Extended Servo Algorithm (ESA) may be used instead of the PID filter. The choice of servo filter may be
made on a motor-by-motor basis.
The ESA, while more powerful and flexible than the PID, is not as easy to understand or tune
interactively. The PEWIN32PRO Executive program has auto-tuning software for the ESA. However,
tuning the ESA manually requires significant control-theory knowledge and experience. This discussion
assumes such knowledge.
The ESA has 30 terms in seven blocks of polynomial coefficients. As with the PID, it does support single
and dual feedback using the Ixx03 and Ixx04 feedback address variables. However, the ESA is more
flexible with regard to what is done with dual feedback; it is not limited to separate position and velocity
loops. The feedback selected with Ixx03 and the commanded trajectory values are pre-multiplied by the
Ixx08 scale factor; the feedback selected with Ixx04 is pre-multiplied by the Ixx09 scale factor.
As with the PID, or a user-written servo, the ESA can be used with or without Turbo-PMAC based
commutation. If the motor is not commutated by Turbo PMAC, the computed control output is written to
the register specified by Ixx02; if it is commutated by Turbo PMAC, the control output is the torque
(quadrature) command into the commutation algorithm.
Extended Servo Algorithm (ESA) may be used instead of the PID filter. The choice of servo filter may be
made on a motor-by-motor basis.
The ESA, while more powerful and flexible than the PID, is not as easy to understand or tune
interactively. The PEWIN32PRO Executive program has auto-tuning software for the ESA. However,
tuning the ESA manually requires significant control-theory knowledge and experience. This discussion
assumes such knowledge.
The ESA has 30 terms in seven blocks of polynomial coefficients. As with the PID, it does support single
and dual feedback using the Ixx03 and Ixx04 feedback address variables. However, the ESA is more
flexible with regard to what is done with dual feedback; it is not limited to separate position and velocity
loops. The feedback selected with Ixx03 and the commanded trajectory values are pre-multiplied by the
Ixx08 scale factor; the feedback selected with Ixx04 is pre-multiplied by the Ixx09 scale factor.
As with the PID, or a user-written servo, the ESA can be used with or without Turbo-PMAC based
commutation. If the motor is not commutated by Turbo PMAC, the computed control output is written to
the register specified by Ixx02; if it is commutated by Turbo PMAC, the control output is the torque
(quadrature) command into the commutation algorithm.