Marine Current

5-phase PMSG

DC

AC

V ωr (k) θe (k)

Is-abcde (k) u1 (k), u2 (k) ESS

N

DC

AC

Ig-abc (k)

ia ib

ic

Lg Rg

690 V (RMS) 50Hz

10

7.5

5.0

2.5

0

Tid

al s

peed

(m/s

ec)

0 0.5 1.0 1.5 2.0 2.5 3.0 3.5

Time (h)

0 0.5 1.0 1.5 2.0 2.5 3.0 3.5

Time (h)

12

10

8

6

4

2

12

10

8

6

4

2

Tid

al to

rque

(Nm

) A

ngul

ar v

eloc

ity (m

/sec

)

Unconstrained

With torque and power limits

(a)

(b)

0 0.5 1.0 1.5 2.0 2.5 3.0 3.5

Time (h)

Pmax

Tmax

Gen

erat

or to

rque

(Nm

) G

ener

ator

pow

er (W

)

1400

1200

1000

800

600

400

200

1400

1200

1000

800

600

400

200

(a)

(b)

4

3

2

1

With swell

Without swell

Cur

rent

spe

ed (m

/sec

)

Time (sec)

0 50 100 150 200 250 300

0 2 4 6 8 10 12 14

Time (sec)

Pow

er (W

)

2

1

0

-1

-2

-106

With supercapacitor-based ESS

Without supercapacitor-based ESS

0 2 4 6 8 10 12 14 Time (sec)

Reference

Normal operation

Voltage sag of 50% Voltage interruption

3.0

2.5

2.0

1.5

1.0

Rot

or s

peed

ωr (

rad/

sec)

2000

1000

0

2000

1000

0

µ 2 (V

)

0 2 4 6 8 10 12 14

µ 2 (V

)

(a)

(b)

Normal operation Voltage sag of 50%

Voltage interruption

Time (sec)

-105

6

4

2

0

Normal operation

Voltage sag of 50%

Voltage interruption

Time (sec)

5 5.01 5.02 5.03 5.04 5.05

200

0

-200

Cur

rent

s (A

) C

urre

nts

(A)

Cur

rent

s (A

)

(a)

(b)

(c)

200

0

-200

200

0

-200

2

1

0

-1

Rea

ctiv

e po

wer

(Var

)

Normal operation Voltage sag of 50% Voltage interruption

-105

Normal operation

Voltage sag of 50%

Voltage interruption

0 2 4 6 8 10 12 14 Time (sec)