# Time Domain Investigation of Hybrid Intelligent Controllers Fed Five-Phase PMBLDC Motor Drive
## 4 Simulation and Discussion
### ANFIS-Controller-Driven Drive
#### 4.5.2 Step or Gradual Application and Removal of Load  
The performance speed characteristic of instant loading gives a settling time of 1.19 s with a \(-\)2.21% overshoot (\(-\)3.42% for PI, \(-\)0.142% for fuzzy, and \(-\)5.5% for fuzzy-PI) \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Load** & \multirow{2}{*}{**Characteristics**} & **Time** & \multirow{2}{*}{**Overshoot \%**} & **Feak Time (s)** & **Rise** & **Settling** & **Steady** \\
**Variation** & & & **Interval (s)** & & **Time (s)** & **Time (s)** & **State Error** \\ \hline \multirow{4}{*}{
\begin{tabular}{c} Linear \\ load \\ variation \\ \end{tabular} } & Starting & 0–1 & 4.9 & 0.1599 & 0.0993 & 0.1778 & \(-\)2 rpm \\  & Loading & 1–1.2 & \(-\)5.5 & 1.001 & 0.1271 & 1.1950 & 71 rpm \\  & Unloading & 3.3–3.5 & 0.2011 & 3.3146 & 0.00012 & 3.499 & 84 rpm \\  & Load removal & 3.5–5 & 5.155 & 3.5404 & 0.0165 & 4.999 & \(-\)2 rpm \\  & Starting & 0–1 & 4.9 & 0.1559 & 0.0993 & 0.1778 & \(-\)2 rpm \\  & Gradual increases of load & 1–2.5 & \(-\)4.5 & 2.1742 & 0.1962 & 2.4980 & 59 rpm \\  & Constant Max Load & 2.5–3.5 & 2.25 & 2.5008 & 0.1884 & 3.4988 & 87 rpm \\  & Gradual decrease in load & 3.5–4.5 & 3.033 & 3.8669 & 0.1992 & 4.497 & 1 rpm \\  & No Load & 4.5–5 & 0.033 & 4.5778 & 0.0025 & 4.999 & \(-\)1 rpm \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Fuzzy-PI Controller Characteristics. Figure 8: Transient performance of the drive with fuzzy-PI controller. between 1 s to 1.2 s. While unloading, the overshoot is \(-1\)% (22.27% for PI, 0.14% for fuzzy and \(-0.2\)% for fuzzy-PI) with a settling time of 3.49 s. When the load is proportionately increased from 1 s to 2.5 s to 2 nm, the settling time is 2.422 s with a 16 rpm steady state error (135 rpm for PI, 3 rpm for fuzzy, and 59 rpm for fuzzy-PI), with a \(-2.42\)% (1 s to 1.2 s) overshoot. After 2.5 s and up to 3.5 s, when loaded to its steady state value of 2 nm, it has a settling time of 3.47 s. Between 3.5 to 4.5 s, the load starts linearly reducing and it decays instantly down with an overshoot of \(-0.928\), a 10 rpm error, and a settling time of 4.47 s. The motor is unloaded after 4.5 s.  
The torque speed characteristics of the PMBLDC motor fed from different controllers are shown in Figure 10. It is seen that, for a PI controller, the peak motor torque is 7 nm at a speed of 256 rpm, and settles down at 1400 rpm at 0.9 nm. The torque bandwidth (7 Nm-0.9 nm) is 6.1 nm. The fuzzy controller gives a peak motor torque of 12.4 nm at a speed of 244 rpm and settles down at 0.6 nm at 1400 rpm. The torque bandwidth is 11.8 nm. The fuzzy-PI controller has a torque bandwidth of (10.68-0.6) 10.08 nm. The ANFIS controller has a torque bandwidth of (12.12-1.1) 11.02 nm. The peak torque is high at starting for a fuzzy controller and its bandwidth is more compared with other controllers. The ANFIS controller does not attain a steady state speed and settles at 1390 rpm. Based on the above discussion for high torque requirements, at low speed, such as in electric vehicle applications, the ANFIS controller is preferred, as summarized in Table 6. After a series of jerks, the torque and speed settle down