Delta Tau GEO BRICK DRIVE Manuale Utente
Geo Brick Drive User Manual
Motor Setup
210
AC Induction (Asynchronous) Motor Setup
– Without Encoder, Direct
Micro-Stepping
Before you start
The AC Induction Motor Setup section is conceived for Motor#4, which is most commonly used
in Geo Brick Drive applications as a Spindle.
in Geo Brick Drive applications as a Spindle.
Parameters with comments ending with -User Input require the user to enter information
pertaining to their system/hardware.
pertaining to their system/hardware.
For an AC Induction Motor with no encoder, we will use the direct microstepping technique for direct
PWM motor control. This technique creates a simulated position sensor and feedback loop by numerically
integrating the (velocity) command output from the servo loop. This integration requires two entries in the
encoder conversion table. The resulting simulated position value can be used for both motor phase
commutation and servo-loop feedback.
Encoder Conversion Table Setup
The first entry in the encoder conversion table (ECT) for each Induction Motor must read the servo-loop
output like an absolute encoder. This is done with a “parallel-read” entry of a Y/X double register (the
data is in X), unshifted and unfiltered; specifying the use of 24 bits of the 48-bit Y/X register, starting 24
bits from the low end. This is effectively like reading a 24-bit DAC register.
output like an absolute encoder. This is done with a “parallel-read” entry of a Y/X double register (the
data is in X), unshifted and unfiltered; specifying the use of 24 bits of the 48-bit Y/X register, starting 24
bits from the low end. This is effectively like reading a 24-bit DAC register.
The second entry in the ECT for each Ac Induction motor integrates the result of the first entry.
1- Find an open ECT, or preferably go to the
end of Table.
2- Choose Conversion Type, Width in Bits
and Offset Location (as shown)
3- Choose No Shifting, then enter the source
address corresponding to the
channel/motor # (see table below)
channel/motor # (see table below)
4- Click Download Entry
1- Go to the Next Entry
2- Choose Conversion Type, enter previous
entry number, delete the source address and
disable the use of second entry (as shown)
disable the use of second entry (as shown)
3- Click Download entry, and record the
processed data address (i.e. X:$350B). This
is where the commutation and position
simulated encoder data is generated.
is where the commutation and position
simulated encoder data is generated.