**7. Simulation of wind station with one-mass and two-mass shaft turbine models**

The results of simulations of a simple grid, fixed-speed induction machine, and one-mass and two-mass shaft turbines are given in Tables 8 -10 and Figs. 16–42. For an induction wind generator using the induction block in SIMULINK with high voltage sag i.e. 50% with fre‐ quencies 50 and 52 and equal to 13, *C <sup>p</sup>* becomes negative, and the results are unrealistic. Then results of 50% voltage sag are realistic in new simulation of induction machine in Ta‐ bles 8 -10.


**Table 8.** Simulation results by SIMULINK for one and two mass shaft model for *Vsag*= 10%


**Table 9.** Simulation results by SIMULINK for one and two mass shaft model for *Vsag*= 20%


**Table 10.** Simulation results by SIMULINK for one and two mass shaft model for *Vsag*= 50%

**Figure 15.** Electrical torque when *f <sup>s</sup>*= 52 and υ*w*= 13m/s.

**models**

44 Advances in Wind Power

bles 8 -10.

**7. Simulation of wind station with one-mass and two-mass shaft turbine**

The results of simulations of a simple grid, fixed-speed induction machine, and one-mass and two-mass shaft turbines are given in Tables 8 -10 and Figs. 16–42. For an induction wind generator using the induction block in SIMULINK with high voltage sag i.e. 50% with fre‐ quencies 50 and 52 and equal to 13, *C <sup>p</sup>* becomes negative, and the results are unrealistic. Then results of 50% voltage sag are realistic in new simulation of induction machine in Ta‐

υ*<sup>w</sup> f <sup>s</sup>*= 48 *f <sup>s</sup>*= 50 *f <sup>s</sup>*= 52

**Table 8.** Simulation results by SIMULINK for one and two mass shaft model for *Vsag*= 10%

ω*<sup>m</sup> pu Te pu* ω*<sup>m</sup> pu Te pu* ω*<sup>m</sup> pu Te pu*

6 .9624 -.1152 1.0024 -.106 1.0423 -.097 10 .9703 -.516 1.0111 -.5128 1.0519 -.5071 13 .9757 -.795 1.0176 -.8201 1.0595 -.8399

**Figure 16.** Torque-time in per unit while *Vsag*= 10% and υ*w* = 6m/s, *f <sup>s</sup>*=48

**Figure 17.** Torque-time in per unit while *Vsag*= 10% and υ*w* = 10m/s, *f <sup>s</sup>*= 48

**Figure 18.** Torque-time in per unit while *Vsag*= 10% and υ*w* = 13m/s, *f <sup>s</sup>*= 48

**Figure 19.** Torque-time in per unit while *Vsag*= 20% and υ*w* = 6m/s, *f <sup>s</sup>*= 48

**Figure 17.** Torque-time in per unit while *Vsag*= 10% and υ*w* = 10m/s, *f <sup>s</sup>*= 48

46 Advances in Wind Power

**Figure 18.** Torque-time in per unit while *Vsag*= 10% and υ*w* = 13m/s, *f <sup>s</sup>*= 48

**Figure 20.** Torque-time in per unit while *Vsag*= 20% and υ*w* = 10m/s, *f <sup>s</sup>*= 48

**Figure 21.** Torque-time in per unit while *Vsag*= 20% and υ*w* = 13m/s, *f <sup>s</sup>*= 48

**Figure 22.** Torque-time in per unit while *Vsag*= 50% and υ*w* = 6m/s, *f <sup>s</sup>*= 48

**Figure 23.** Torque-time in per unit while *Vsag*= 50% and υ*w* = 10m/s, *f <sup>s</sup>*= 48

**Figure 21.** Torque-time in per unit while *Vsag*= 20% and υ*w* = 13m/s, *f <sup>s</sup>*= 48

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**Figure 22.** Torque-time in per unit while *Vsag*= 50% and υ*w* = 6m/s, *f <sup>s</sup>*= 48

**Figure 24.** Torque-time in per unit while *Vsag*= 50% and υ*w* = 13m/s, *f <sup>s</sup>*= 48

**Figure 25.** Torque-time in per unit while *Vsag*= 10% and υ*w* = 6m/s, *f <sup>s</sup>*= 50

**Figure 26.** Torque-time in per unit while *Vsag*= 10% and υ*w* = 10m/s, *f <sup>s</sup>*= 50

**Figure 27.** Torque-time in per unit while *Vsag*= 10% and υ*w* = 13m/s, *f <sup>s</sup>*= 50

**Figure 25.** Torque-time in per unit while *Vsag*= 10% and υ*w* = 6m/s, *f <sup>s</sup>*= 50

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**Figure 26.** Torque-time in per unit while *Vsag*= 10% and υ*w* = 10m/s, *f <sup>s</sup>*= 50

**Figure 28.** Torque-time in per unit while *Vsag*= 20% and υ*w* = 6m/s, *f <sup>s</sup>*= 50

**Figure 29.** Torque-time in per unit while *Vsag*= 20% and υ*w* = 10m/s, *f <sup>s</sup>*= 50

**Figure 30.** Torque-time in per unit while *Vsag*= 20% and υ*w* = 13m/s, *f <sup>s</sup>*= 50

**Figure 31.** Torque-time in per unit while *Vsag*= 50% and υ*w* = 6m/s, *f <sup>s</sup>*= 50

**Figure 29.** Torque-time in per unit while *Vsag*= 20% and υ*w* = 10m/s, *f <sup>s</sup>*= 50

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**Figure 30.** Torque-time in per unit while *Vsag*= 20% and υ*w* = 13m/s, *f <sup>s</sup>*= 50

**Figure 32.** Torque-time in per unit while *Vsag*= 50% and υ*w* = 10m/s, *f <sup>s</sup>*= 50

**Figure 33.** Torque-time in per unit while *Vsag*= 50% and υ*w* = 13m/s, *f <sup>s</sup>*= 50 in new simulation of wind generator

**Figure 34.** Torque-time in per unit while *Vsag*=10% and υ*w* = 6m/s, *f <sup>s</sup>*= 52

**Figure 35.** Torque-time in per unit while *Vsag*=10% and υ*w* = 10m/s, *f <sup>s</sup>*= 52

**Figure 33.** Torque-time in per unit while *Vsag*= 50% and υ*w* = 13m/s, *f <sup>s</sup>*= 50 in new simulation of wind generator

**Figure 34.** Torque-time in per unit while *Vsag*=10% and υ*w* = 6m/s, *f <sup>s</sup>*= 52

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**Figure 36.** Torque-time in per unit while *Vsag*= 10% and υ*w* = 13m/s, *f <sup>s</sup>*= 52

**Figure 37.** Torque-time in per unit while *Vsag*= 20% and υ*w* = 6m/s, = 52

**Figure 38.** Torque-time in per unit while *Vsag*= 20% and υ*w* = 10m/s, *f <sup>s</sup>*= 52

**Figure 39.** Torque-time in per unit while *Vsag*= 20% and υ*w* = 13m/s, *f <sup>s</sup>*= 52

**Figure 37.** Torque-time in per unit while *Vsag*= 20% and υ*w* = 6m/s, = 52

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**Figure 38.** Torque-time in per unit while *Vsag*= 20% and υ*w* = 10m/s, *f <sup>s</sup>*= 52

**Figure 40.** Torque-time in per unit while *Vsag*= 50% and υ*w* = 6m/s, *f <sup>s</sup>*= 52

**Figure 41.** Torque-time in per unit while *Vsag*= 50% and υ*w* = 10m/s, *f <sup>s</sup>*= 52

**Figure 42.** Torque-time in per unit while *Vsag*= 50% and υ*w* = 13m/s, *f <sup>s</sup>*= 52 in new simulation of wind generator
