WEG ECW500, Руководство пользователя

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Functional Description .
ECW500 | 55
This parameter defines the percentage variation that will be imposed to the ECW500 output during the
Autotuning procedure. This percentage is related with the current duty cycle ratio value (40062).
Example:
If the ECW500 is operating with duty cycle (40062) of 35% and an excitation voltage (40046) of 13.5 Volts, an
Output Level Variation adjusted in 5.0% will make that duty cycle swing between 36.75% (35% * 1.05) and
33.25% (35*0.95) during the Autotuning. The excitation voltage, in this case, must swing between 14.2V and
12.8V (13.5% ± 5%).
It's possible to adjust high values for
Output Level Variation, since that the oscillation generated in machine s
voltage and current doesn t cause damage to application.
In practical terms this means that the higher
Output Level Variation the easier the Autotuning function be
executed with success.
<31072>
Hysteresis Level (Hyster.AT)
This parameter defines the percentage of
hysteresis that must exist on the feedback signal for the control to
impose the change of duty cycle.
Example:
If the ECW500 is working in MTVC mode with a feedback voltage in 13800V, a
hysteresis of 0.5% specify that
the autotuning must to wait an identification of the voltage feedback over of 13869 V (13800V * 1.005) and
under of 13731 V (13800V * 0.995) to change the duty cycle between the levels defined by 31070.
For the autotuning routine, the lower the hysteresis the closer of the ideal values the gains will be calculated.
However, in the practice, a low value of
hysteresis can let the autotuning routine very sensitive and maybe it will
not be possible to achieve the convergence. So, the rule for this parameter is to start with the standard value
(0.5%). In case that the autotuning finishes without to find the gains of controller, it must be increased the value
slowly.
<31074>
Convergence Tolerance (Converg.)
This parameter defines the maximum level of offset between the measures performed during the autotuning, for
purpose of convergence.
In most of applications, the standard value 2.5% is enough for the Autotuning be completed with success. This
value must be raised only if, after a few tries, the function does not obtain the gains of controller.
<31076> Autotuning Execution Timeout (TimeoutAT)
This parameter establishes the maximum time that the Autotuning routine will be in execution to find the gains of
the controller. If the limit time is reached without any convergence, the autotuning will be closed and the duty
cycle will be back at the original value before the beginning of the routine.
The limit time of 20 seconds normally is enough for the Autotuning converge to some result. If the function does
not achieve the gains and does not create a dangerous situation to the application, this limit time can be
increased gradually.
<31078>
Autotuning Proportional gain (ATune Kp)
<31080> Autotuning Integral gain (ATune Ki)
<31082>
Autotuning Derivative gain (ATune Kd)
These parameters store the calculated values for the controller gains after a successful execution of Autotuning
routine.
If the Autotuning does e to any result during your execution time, these parameters will be set to null
(0).
<31084>
Controller Configuration (Conf. Ctrl)