Stabilizing an Unstable Position Controller


Stabilizing an Unstable Position Controller

For a properly designed system, the transient response effect should gradually decay within a few seconds, and the system should reach a steady state operation. However, for an improperly designed system, the transient response can lead into an oscillation which can be sustained over a long period of time. Such a system is unstable and should be corrected for a stable operation.

The instability of a system is mainly caused by either a long time constant in the system or an excessive gain in the system. A closed loop speed controller can mitigate oscillation up to certain extent. However, in case a highly stable system is desired with a maximum gain, the system needs more advanced technique than a simple speed control loop. The experiment in this section is limited to a speed controlled stabilization method. The same experiment system as in the previous section is used for this experiment.

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