User manual

Feature Configuration
ANCA Motion DS619-0-00-0019 - Rev 0 129
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10.1.22 Motor Control
Description
The AMD2000 control loops utilise the architecture for position, velocity and torque/current control displayed by
Figure 10-20.
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At ANCA Motion the term Motor Control refers to the current control loop, the torque gain
scheduler, and all of the appropriate switches to toggle between a variety of magnetic field alignment methods. A
high level view of the Motor Control and its context within the AMD2000 control architecture is displayed in Figure
10-21. It is clear from these diagrams that the accuracy of the position and velocity controllers must, in part, be
determined by the Motor Control.
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Position
Controller
q
~
q
*
q
Velocity
Controller
w
~
w
*
w
Torque
Control
t
*
Current
Controller
(q-axis)
i
q
~
i
q
*
i
q
Current
Controller
(q-axis)
i
d
*
i
d
~
i
d
v
q
*
v
d
*
Figure 10-20 Cascaded control architecture found in IEC 61491
As the name is intended to imply, the Motor Control portion of the control loops is intimately related to the type of
motor under control. The AMD2000 supports control for two dominant types of motor type;
1. Permanent Magnet Synchronous Motors, or
2. Induction Motors.
ANCA Motion’s approach to implementing Motor Control is broken down into a number of sub-systems that must
all be configured correctly if they are to be used effectively in controlling either of these two motor types. The two
dominant sub-systems of concern to the user are the,
 Torque controller, and the
 Current controller.
Torque and current are intimately related to one another, where the relationship between torque,  and q-axis
motor current, 

 is described using a units scaling (or proportional gain) 

, as follows;
  



The AMD2000 makes some special assumptions in order to simplify this relationship further. For this drive


  under all conditions, except for Field Weakening (see below for details). Under this condition the torque
and current control commands are the same value.
However, as far as the servo control architecture is concerned, the two physical quantities remain distinct. As a
consequence, it is necessary for the user to select the appropriate motor type for both the torque and current
controller subsystems separately.
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The AMD2000 allows for the SoE profile to be applied to data communications with an external EtherCAT device.
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Details for the motivation in having two current controllers, one for “quadrature” and one for “direct” current (so-called q and d currents), is given
elsewhere in this user manual under the section title “Field Orientation Initialisation.”
Motor Control