*Enhanced Nonlinear PID Controller for Positioning Control of Maglev System DOI: http://dx.doi.org/10.5772/intechopen.96769*

tests are carried out at various levitation displacements. **Figure 4** depicts the system driving characteristic that is measured and adopted as a model-based feedforward control in the proposed controller.

**Figure 5** shows the step responses of the PI-PD and FF PI-PD controllers at 0.5 mm and 1.0 mm step inputs. In contrast to the PI-PD controller, the FF PI-PD controller demonstrates a better overshoot reduction characteristic. Besides, the FF PI-PD controller positioning time is shorter than the PI-PD controller. The comparative experimental performances show that the model-based feedforward control improves the overshoot reduction characteristic.
