MOOG
ID
No.: CB40859-001 Date: 02/2018
MSD Servo Drive- Device Help
129
7 Control
matrix P353[1] - CON_SCALC_ObsDesignPara. The objective is to bring the
estimated state variables into equivalence with the measurements as quickly as
possible.
NOTE
PleasecontactMoogbeforeconfiguringtheobserver.
7.4.1.2Reductionofgainatlowspeeds.
With speed controllers set to be very dynamic, undesirable oscillation of the speed
controller may occur at low speeds or at zero speed. An appropriate setting of P336
- CON_SCON_KpScaleSpeedZero reduces this tendency to oscillate.
Fig. 7.22: Reduction of gain at low speeds.
7.4.1.3Quickstopwithoutsensor
In the event of a wire break on the encoder system the drive is shut down in
sensorless mode on the preset quick-stop ramp (see Section "Error reactions" on
page 266 and Section "Stop ramps" on page 187). Due to the lack of dynamism at low
speeds, the sensorless control is very "imprecise". To enable the drive nevertheless to
be run down smoothly to speed 0, as from the speed threshold parameterized in
P355[0] - LowSpeedLimit the controller switches to a
current/frequency (IF) control. For stabilization, an additional, cumulative d-current
must be injected that can be set via the P355[1] - d-current Injection parameter. The
speed controller gain is reduced by the factor P355[2] - SpeedControlGainScale.
Fig. 7.23: Quick stop without sensor