PSI- Issue 9

Mohammed Ezzahi et al. / Procedia Structural Integrity 9 (2018) 221–228 Author name / Structural Integrity Procedia 00 (2018) 000–000

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4

4. Modeling of the Doubly Fed Induction Generator (DFIG) in the (d-q) frame: In this paper, we will proceed to modeling the DFIG in the rotating (d-q) frame Salloum (2007). Therefore, the equations in the (d-q) frame of PARK transformation are given by many equations expressing the current and the magnetic field. For the stator, we find the equations blow:



. V R i ds

s ds  



  

(1)

.

.

ds

s qs

t





. V R i qs

s ds  



  

(2)

.

.

qs

s ds

t



s ds .    .    ds L i s qs qs L i

M i . M i .

(3)

dr

(4)

qr

For the rotor side, we find the equations below:



. V R i dr

r dr  



  

(5)

.

.

dr

r qr

t





. V R i qr

r dr  



  

(6)

.

.

qr

r dr

t



r dr .    .    dr L i r qr qr L i

M i . M i .

(7)

ds

(8)

qs

The stator and the rotor parameters are expressed according to each other:    . p s r  

(9)

r s L l M   s r L l M  

(10)

s

(11)

r

From all the equation above, we express the active and the reactive powers:

ds ds .   .   qs ds dr dr .   .   qr dr

V i .

s P V i s Q V i r P V i r Q V i

(12)

qs qs

V i .

(13)

d s qs

V i .

(14)

qr qr

V i .

(15)

dr qr

5. Field Oriented Control (FOC) Field oriented control (FOC) or vector control is commonly used in DFIG controls due to its ability of controlling the motor speed more efficiently, and due to its lower cost of building. FOC controls separately the active and the