**5.1 Test system 1**

44 Electrical Generation and Distribution Systems and Power Quality Disturbances

1 *NW*

*NG NW*

1 1

12 *Pd Pd PD* + = (36)

*i i Pd Pd Pg Pw P* = =

Where, *<sup>l</sup> <sup>N</sup>* is the number of transmission lines; *<sup>k</sup> g* is the conductance of branch *k* between buses *i* and *j*; *<sup>k</sup> t* the tap ration of transformer *k*; *Vi* is the voltage magnitude at bus *i; ij*

Pg2 Pg3 PgN

*Pd1=80% PD* 

*Length of Vector Control* 

max *Pw*

The inequality constraints to be satisfied are all the security constraints related to the state

Fig. 12 shows the two coordinated vectors control structure related to this stage, the

The proposed algorithm is developed in the Matlab programming language using 6.5 version. The proposed approach has been tested on many practical electrical test systems (small size:

individual of the combined vector control denoted by *X P PQ Q pq w wN STC STCN* = [ 1 1 ,..., , ,..., ] Where [*P P w wN* <sup>1</sup> ,..., ] indicate active power outputs of all units based wind source, [*Q Q STC STCN* <sup>1</sup> ,..., ] represent reactive power magnitude settings of all STATCOM controllers

min *QStatcom*

*i Pd Pw* =

*i*

*i i loss*

<sup>=</sup> (34)

δthe

+− − = (35)

*Length of Vector Control* 

*PD* 

*QSTC*

*QSTC QSTC QSTC*

 *1 2 NStc* 

*Length of Vector Control* 

*NW=NStc* 

max *QStatcom*

max *Pg*

2

1 2

voltage angle difference between buses *i* and *j.* 

min *Pg*

varaibles and the control variables mentioned in section 2.1.

Fig. 11. Vector control structure: conventional source

*Pw1 Pw2 Pwn* 

 *1 2 NW* 

*Pd2<=20% PD* 

min *Pw*

Fig. 12. Coordinated vector control

exchanged with the network.

**5. Simulation results** 

The first test system has 6 generating units; 41 branch system, the system data taken from (). It has a total of 24 control variables as follows: five units active power outputs, six generator-bus voltage magnitudes, four transformer-tap settings, nine bus shunt FACTS controllers (STATCOM). The modified IEEE 30-Bus electrical network is shown in Fig 13.

Fig. 13. Single line diagram for the modified IEEE 30-Bus test system (with FACTS devices)

Optimal Location and Control of

**676**

**0**

Condition: IEEE 30-Bus

**20**

**40**

**60**

**80**

**Power Transit (Pij)**

**100**

**120**

**140**

source and STATCOM

**678**

**680**

**682**

**684**

**Cost (\$/h)**

**686**

**688**

**690**

**692**

**694**

Multi Hybrid Model Based Wind-Shunt FACTS to Enhance Power Quality 47

**0 20 40 60 80 100**

**With Wind-Statcom**

**Without: Wind/Statcom**

**Pij Max**

**Iteration**

**0 5 10 15 20 25 30 35 40 45**

**Branches (i-j)**

Fig. 15. Active power transit (Pij) with and without wind and STATCOM, Case1: Normal

Fig. 14. Convergence characteristic of the 6 generating units with consideration of wind


#### **Case1: Normal Condition**

Table 1. Power Quality Results based Hybrid Model: Wind Source: STATCOM: IEEE-30Bus: Normal Condition

STATCOM **10 12 15 17 20 21 23 24 29** 

Q (MVAR) 35.92 -16.27 -9.82 -19.34 -1.96 -19.94 1.25 4.82 -4.25

Pw (MW) 3.9194 3.9202 4.0070 4.0615 4.1781 4.1956 3.9707 3.8700 3.8776

V (p u) 1.02 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0

Ploss (MW) **7.554** 

Cost (\$/h) **676.4485** 

**Buses** 

**36 (12.7%), PD =283.4 MW** 

> **Case1 Normal Condition**

**254.95 (89.96%)** 

Table 1. Power Quality Results based Hybrid Model: Wind Source: STATCOM: IEEE-30Bus:

**Case1: Normal Condition** 

1 *NW w i P* = 

(MW)

Pg1 (MW) 149.92

Pg2 (MW) 46.53

Pg5 (MW) 20.64

Pg8 (MW) 15.81

Pg11(MW) 10.05

Pg13(MW) 12

Qg1 5.39

Qg2 21.67

Qg5 23.04

Qg8 45.77

Qg11 15.43

Qg13 39.09

Normal Condition

1 *NG G i P* = 

(MW)

Fig. 14. Convergence characteristic of the 6 generating units with consideration of wind source and STATCOM

Fig. 15. Active power transit (Pij) with and without wind and STATCOM, Case1: Normal Condition: IEEE 30-Bus

Optimal Location and Control of

 = *NW i Pw* 1 (MW)

Pg1 (MW) 64.12

Pg2 (MW) 67.98

Pg5 (MW) 26.86

Pg8 (MW) 34.65

Pg11(MW) 21.00

Pg13(MW) 20.24

Qg1 1.76

Qg2 41.3

Qg5 20.98

Qg8 35.55

Qg11 8.08

Qg13 39.26

 = *NG i PG* 1 (MW)

Multi Hybrid Model Based Wind-Shunt FACTS to Enhance Power Quality 49

STATCOM **10 12 15 17 20 21 23 24 29** 

Q (MVAR) 42.76 -15.65 -11.00 -20.10 -2.90 -20.83 0.28 4.09 -4.52

Pw (MW) 5.8791 5.8803 6.0105 6.092 6.2671 6.2934 5.9560 5.8050 5.8164

V (p u) 1.02 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0

Ploss (MW) **5.449** 

Cost (\$/h) **686.1220** 

**Buses** 

**54 MW (19.05%), PD =283.4 MW** 

> **Abnormal Condition Without line 1-2**

**235.610MW (83.14%)** 

Table 2. Power Quality Results based Hybrid Model: IEEE-30Bus: Abnormal Condition

Table 1 shows the results based on the flexible integration of the hybrid model, the goal is to have a stable voltage at the candidate buses by exchanging the reactive power with the network, the active power losses reduced to 7.554 MW compared to the base case: 10.05 MW, without integration of the hybrid controllers, the total cost also reduced to 676.4485 \$/h compared to the base case (802.2964 \$/h), Fig. 14 shows the convergence characteristic of fuel cost for the IEEE 30-Bus with consideration of the hybrid models, Fig. 15 shows the distribution of power transit in the different branches at normal condition, Fig. 17 shows the distribution of power transit in the different branches at contingency situation (without line 1-2).

The active power transit reduced clearly compared to the case without integration of wind source which enhance the system security. Fig. 16 shows the improvement of voltage profiles based hybrid model. Results at abnormal conditions (contingency) are also encouragement.

Fig. 16. Voltage profiles with and without hybrid model (wind and STATCOM): IEEE 30-Bus

#### **Case2: Under Contingency Situation**

The effeciency of the integrated hybrid model installed at different critical location is tested under contingency situation caused by fault in power system, so it is important to maintain the voltage magnitudes and power flow in branches within admissible values. In this case a contingency condition is simulated as outage at different candidate lines. Table 2 shows sample results related to the optimal power flow solution under contingency conditions **(***Fault at line 1-2***).**

Table 1 shows the results based on the flexible integration of the hybrid model, the goal is to have a stable voltage at the candidate buses by exchanging the reactive power with the network, the active power losses reduced to 7.554 MW compared to the base case: 10.05 MW, without integration of the hybrid controllers, the total cost also reduced to 676.4485 \$/h compared to the base case (802.2964 \$/h), Fig. 14 shows the convergence characteristic of fuel cost for the IEEE 30-Bus with consideration of the hybrid models, Fig. 15 shows the distribution of power transit in the different branches at normal condition, Fig. 17 shows the distribution of power transit in the different branches at contingency situation (without

The active power transit reduced clearly compared to the case without integration of wind source which enhance the system security. Fig. 16 shows the improvement of voltage profiles based hybrid model. Results at abnormal conditions (contingency) are also

Without/Wind, STATCOM **Max V** 

With Wind-STATCOM

**0 5 10 15 20 25 30**

**Bus N°**

The effeciency of the integrated hybrid model installed at different critical location is tested under contingency situation caused by fault in power system, so it is important to maintain the voltage magnitudes and power flow in branches within admissible values. In this case a contingency condition is simulated as outage at different candidate lines. Table 2 shows sample results related to the optimal power flow solution under contingency conditions

Fig. 16. Voltage profiles with and without hybrid model (wind and STATCOM):

**Min V** 

line 1-2).

encouragement.

**0.92**

**Case2: Under Contingency Situation** 

IEEE 30-Bus

**(***Fault at line 1-2***).**

**0.94**

**0.96**

**0.98**

**1.02**

**Voltage (pu)**

**1.04**

**1.06**

**1.08**

**1.1**

**1**


Table 2. Power Quality Results based Hybrid Model: IEEE-30Bus: Abnormal Condition

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