Operation & Software Manual
18
Direct Drives & Systems
Chapter A: Internal functioning & architecture
ETEL Doc. - Operation & Software Manual # DSC2P 903 / Ver. F / 3/6/05
1.
The regulators
Two Digital Signal Processors (DSP, Sharc from Analog Devices) manage the controller. The first manages
the movements profiles and the second is used for the regulation loops. There are two regulation loops, a
position loop
and a
current loop
,
controlled by the second DSP. The position loop calculates the
reference
force F
c
that the motor supplies to follow the position reference calculated in a separated generator, called
set
point generator
. This force is afterwards sent to the current loop where the
current reference generator
calculates the reference currents
I
cx
for each motor phase. Those references are eventually sent to a PI
(proportional-integral) regulator which controls the current in the motor phase(s). The diagram below shows the
complete regulation process.
The elements of this
regulation general diagram are detailed in
(for beginners) and in
(for advanced
users).
Set point
generator
User
a
max
v
max
x
final
State regulator
Position
control
Current
reference
generator
PI regulator
Current
control
Motor
Speed
estimator
x
:
Motor real position
V
:
Motor speed
F
:
Force supplied by the motor
I
:
Current in the motor
Kt
:
Motor force constant
x
c
:
Position reference
V
c
:
Speed reference
F
c
:
Force reference
I
c
:
Current reference in the motor
a
c
:
Acceleration reference
Movement manager processor
Regulation (current & position) processor
x
c
V
c
a
c
F
c
I
c
I
Kt
F
I
x
x
V