Analysis of speed control

NAVIGATION: Closed-loop control > Speed control > Analysis of speed control

Analysis of speed control

The speed controller is executed as a PI controller. The gain (P-component) and the integral-action time (I-component) of the individual controllers are programmable.
In order to optimize the speed control loop, two rectangular reference steps are preset.
For automatic controller optimization the step response and transfer function wizards are available.

Bild: Advanced analysis of the speed controller

Vorgehensweise: Optimizing the speed controller

The speed and time settings are generated automatically from the motor data.
ISDSH and ENPO (hardware enable) must be set to "High".
Click "Start test signal" button
Observe the safety notice: When you confirm the safety notice a step response is executed.
The oscilloscope is set automatically.
The faster the actual value approaches the setpoint (reference), the more dynamic is the controller setting. During settling, the overshoot of the actual value should be no more than 5-10% of the reference (guide value).

Bild: Step response to rated speed

Creating the transfer function

The oscilloscope automatically records the amount and phase response of the controller according to the controller settings. This produces an initial estimate of the control quality.

To determine the transfer function the noise amplitude (motor rated current) and the sampling time (default 0.125 ms) must be specified. Click the "Start Test Signal" button.

Bild: Noise amplitude, sampling time

	Green curve = Amount Y-axis left = Absolute value of nact/ndiff
	Blue curve = Phase response Y-axis right = Phase response nact/ndiff

Bild: Speed controller transfer function