Modulation Strategy to Reduce Common-Mode Voltage for Three-to-Five Phase Indirect Matrix Converter - Intelligent Computing for Sustainable Energy and Environment - page 32

q

V

24

11000

V

29

11101

V

26

11010
00000
11111 01001

V

ref

V
31

0 α

V

11001

d

10000

V V V 16 25

(a) Synthesis the reference output voltage vector in sector 1for d 1 − q 1 plane

q

V 29

d

T M 1 V

3

V V

16

T

16

25

S

T

T

L 2 V

M 2 V 24

T 29

T

S

S

T

L 1 V

V

25

T

24

S

(b) The created output voltage vector in sector 1 for d 3 − q 3 plane

Fig. 3. Synthesis the reference output voltage vector in sector 1

large active vectors are used to synthesize the reference output voltage. The duty
ratio of active and zero vectors is[12]

5sin( π/ 5) μ

sin 5 −

α 0

m

d 11001 =

1+ μ 2

5sin( π/ 5) μ

sin( α 0 )

m

d 11000 =

1+ μ 2

5sin( π/ 5) μ

sin 5 −

α 0

(7)

m

d 10000 =

1+ μ 2

5sin( π/ 5) μ

sin( α 0 )

m

d 11101 =

1+ μ 2

d 11111 = d 00000 = 2 (1

− d 11001 − d 11000 − d 10000 − d 11101 )

( π/ 5). m is the modulation index of the inverter stage, m = 2 V om

where μ =2 ·

V dc ,

the maximum modulation index in the inverter stage is

1
cos 10 =1 . 0514

m max = (8)

3.3 Modulation Strategy to Reduce CMV for Three-to-Five Phase
IMC

In a five phase motor driving system, there are inevitable voltage between the
load and the earth. These had previously been ignored voltage is called common
mode voltage u NO , as shown in Fig.4. Obviously has the following relationship