**Scenario 3**

The 1/φ asymmetrical fault was implemented at t = 4.0 s, and then it was cleared at t = 4.5 s, as shown in Figure 7a. The 1/φ asymmetrical fault was lighter than the other fault types. However, the 1/φ asymmetrical fault is the most common type of grid fault. Therefore, the control of this fault type is vital. The IT-2 FLC and T-1 FLC were separately implemented in the system. The parameters of the system that were measured were the rotor speed, DC link (Vdc), electromagnetic torque (Te), and reactive and active power. The maximum value of the rotor speed with the T-1 FLC system was 1.2 p.u., and its drop value was 1 p.u. value, as shown in Figure 7b. The DC link voltage with the T-1 FLC system was 1300 V during the grid fault. The drop value of the active power with the T-1 FLC was 82% p.u., and the overshoot value of the active power with the T-1 FLC was 1.05 p.u. The parameters of the system that were observed were the rotor speed, DC link (*Vdc*), electromagnetic torque (*Te*), and reactive and active power. The rotor speed, DC link (*Vdc*), active power, reactive power, and electromagnetic torque (*Te*) of the system with the IT-2 FLC had near nominal values and are given in Figure 7b–f, respectively. All the parameters of the system with the IT-2 FLC closely tracked the rated values both during and after the grid fault.

**Figure 7.** *Cont*.

**Figure 7.** (**a**–**f**)**.** Dynamic response of a 1.5 MVA permanent magnet synchronous generator (PMSG) with the type-1 fuzzy logic control (T-1 FLC) and interval type-2 fuzzy logic control (IT-2 FLC) systems during a 1/φ unsymmetrical fault.

All the parameters with the proposed control system settled to the rated value within comparatively less time than with the T-1 FLC system. The proposed control system reduced the ripples of all the parameters in the system due to the appropriate selection of IT-2 FLC parameters.
