TDE MACNO MINIOPD EXP User Manual page 27

2.2.2.1 MANAGING SPEED REFERENCE VALUES
The application generates two speed reference values:
One , sysSpeedReference, is a percentage of the maximum speed (set in parameter P65)
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displayed in internal value d33 and on monitor o41.
The other, sysSpeedRefPulses is electrical pulses for a period of PWM. This particular
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reference is used so as not to be lose any pulses if the frequency input is used. Internal
normalization is done with 65536 pulses per mechanical revolution.
After these two reference values have been processed they are added together in order to obtain the
total speed reference value.
2.2.2.2 INVERTING AND LIMITING SPEED REFERENCE VALUES
In the standard application, logic function I12 "Speed reference value inversion", which is assigned
to an input (the default is input 6), or connection P237 are used to invert the reference value
according to the following logic (OR-exclusive):
I12 = 0 P237 = 0
I12 = 1 P237 = 0
I12 = 0 P237 = 1
I12 = 1 P237 = 1
The reference value is inverted before the ramp thus, if the ramp is not disabled, the direction of
rotation changes gradually (default C36=0 and I12=0).
There is another chance, to invert positive speed rotation setting C76=1.
Enabling this function, with the same speed reference and speed measured, the motor rotates in
reverse direction.
Parameters P18 and P19 are used to limit the total reference value within a range set between these
two values; P18 is the maximum limit (positive speed) and P19 is the minimum limit (negative speed).
These two parameters may be set at a range from ± 105%, thus special settings may be used to limit
operation within the 2 quadrants or within just one quadrant.
The following settings are provided by way of example:
P18 = 100.0%
P18 = 30.0%
P18 = 80.0%
P18 = -30.0%
2.2.2.3 2ND ORDER SPEED REGULATOR FILTER
The speed regulator filter can be changed by using a 2nd order one.
To enable this function set C69=1. Parameter P33 will always set the filter time constant in
milliseconds, and thus its natural pulsation, given that internal damping is always set to 0.8 so that
the filter is quick to respond but does not overshoot.
Note that enabling a 2nd order filter means reducing the margin of system stability, hence the filter
time constant value must be thought through carefully before setting so as not to create instability:
User's manual
Reference value not inverted (default values)
Reference value inverted
Reference value inverted
Reference value not inverted
P19 = 100.0%
P19 = 20.0%
P19 = -20.0%
P19 = 60.0%
-100.0% < speed reference value < 100%
-20.0% < speed reference value < 30%
20.0% < speed reference value < 80.0%
-60.0% < speed reference value < -30.0%
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