Baldor Flex+DriveII, Руководство по установке

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B-4 Control System MN1902
B.1.3 Position control (Pulse and Direction)
Setting the control mode to Position Control (Pulse and Direction) configures the FlexDrive II
as a positioning system, as shown in Figure 45, capable of following a position command
signal.
The profiler interprets the pulse and direction signals and uses them to generate
corresponding position, speed and acceleration demand signals.
The position and speed demand signals are fed into a position controller and used, together
with the position measured from the feedback device, to generate a suitable speed demand
signal. If the position controller is tuned correctly, the measured position will accurately track
the position demand.
The speed demand signal from the position controller is fed into the speed controller and used,
together with the speed measured from the feedback device, to generate a torque demand
signal. If the speed controller is tuned correctly, the measured speed will accurately track the
speed demand. To improve the tracking performance of the speed controller, the profiler
acceleration demand is fed in at this point.
Finally, the torque demand signal is fed into a torque controller, which determines the
appropriate amount of current to apply to the windings of the motor. This demand current is
compared with the actual winding current measured from sensors, and a suitable pulse width
modulation (PWM) signal is generated. This PWM signal is fed to the power electronics in the
drive.
Position
controller
Speed
controller
Torque
controller
Power stage
+ motor
Speed
demand
Torque
demand
PWM
Position
Speed
Accn
Profiler
Position reference
(Pulse and Direction)
Measured current
Measured speed
Measured position
Figure 45 - Control structure in Position control (Pulse and Direction)