ICERE 2010 CHILE
International Conference and Fair on Education, Research &
Employment in the Renewable
UNIVERSIDAD
DE SANTIAGO
Brushless
hl
d bl f d induction
doubly-fed
i d
i
generator
controlled by matrix converter for wind energy
applications
A. Muñoz
University of Santiago
Chile
A. Sureda
University of Santiago
Chile
R. Cardenas
University of Santiago
Chile
R. Peña
University of Concepción
Brushless doubly-fed induction generator
controlled by matrix converter for wind energy
applications
UNIVERSIDAD
DE SANTIAGO
Structure of the Presentation
 Elemental devices
 The proposed system
 Experimental system
 Results and conclusions
Brushless doubly-fed induction generator
controlled by matrix converter for wind energy
applications
UNIVERSIDAD
DE SANTIAGO
Elemental devices: Three-Leg Matrix Converter
1
Delta-connected
Delta
connected Capacitors
2
IGBT’s
3
u
v
w
V lt
Voltage
and
d Current
C
t Transducers
T
d
S33
S23
S13
S32
S22
S12
S31
S21
S11
c
b
a
Brushless doubly-fed induction generator
controlled by matrix converter for wind energy
applications
UNIVERSIDAD
DE SANTIAGO
Elemental devices: Brushless System
1
Win profile machine
2
Control machine
3
Power
P
Machine
Brushless doubly-fed induction generator
controlled by matrix converter for wind energy
applications
UNIVERSIDAD
DE SANTIAGO
Proposed Variable Speed Generation System
Brushless doubly-fed induction generator
controlled by matrix converter for wind energy
applications
UNIVERSIDAD
DE SANTIAGO
Coordinate Axis d-q
VB
Vq
Coordinate Axis
Alpha-Beta
Coordinate Axis
A-B-C
V

V dq

120º
Coordinate Axis d-q
Vd
 e
VA
V
VC
Brushless doubly-fed induction generator
controlled by matrix converter for wind energy
applications
UNIVERSIDAD
DE SANTIAGO
M d lli
Modelling
off the
th Brushless
B
hl
DFIG.
DFIG
S11
S12
S13
S21
S22
S23
S31
S32
Rsc
Lscσ
Ψsc
Rrc
Lrcσ
Loe
Ψrc
Rsg
Lsgσ
Ψsg
Lrgσ
Log
Rrg
Ψrg
S33
Matrix Converter
Matrix Converter
G id
Grid
Brushless doubly-fed induction generator
controlled by matrix converter for wind energy
applications
UNIVERSIDAD
DE SANTIAGO
Control System
Ispq *
Ispd *
PI
PI
Iscq *
Iscd *
PI
PI
Vscq
Iscq
Ispq
Iscd
Ispd
LsT
Vscd
LsT
Brushless doubly-fed induction generator
controlled by matrix converter for wind energy
applications
UNIVERSIDAD
DE SANTIAGO
Objetives
 To present a grid connected generation system based on brushless
doubly fed induction machines using a three-leg matrix converter.
 To control the matrix converter (MC) output current, which is
feeding the stator of the control machine , to provide the required
power to the g
p
grid.
 To verify experimentally the strategy considering a system
running
g at below and above synchronous speed by a wind profile.
Experimental System
3x3 Matrix
Converter
3ϕ Variac
HPI
+
FPGA
+
DSP
Host Pc
Grid
3ϕ
Current
Transducers
Voltage
Transducers
Bus
Commercial Inverter
Opto
isolated
Interface
Encoder
board
Cage
Machine
Control DFIG
Grid –Connected
DFIG
Experimental System
Brushless doubly-fed induction generator
controlled by matrix converter for wind energy
applications
UNIVERSIDAD
DE SANTIAGO
Results
The current are well regulated for the whole operating range with a slight increase in the qaxis current error produced when the machine is operating with s  30%.
15
15
Isgq
Isgqref
10
Current [A]
Current [A]
10
5
5
0
0
-5
0
Isgq
Isgqref
0.2
0.4
0.6
0.8
1
 Step change in the torque current iqsg for s=30%.
-5
0
0.2
0.4
0.6
0.8
1
Time[s]
 Step change in the torque current iqsg for s=-30%.
Brushless doubly-fed induction generator
controlled by matrix converter for wind energy
applications
UNIVERSIDAD
DE SANTIAGO
Results
5
15
0
10
Iscq
Iscd
Iscqref
Iscdref
-5
-10
10
-15
Current [A]
Current [A]
Performance of the proposed control system for a speed ramp variation.
Isgq
Isgd
Isgqref
Isgdref
5
0
1
2
3
4
5
6
Time [s]
7
8
 d-q stator current components in the
control DFIG.
9
10
-5
1
2
3
4
5
6
7
8
9
 d-q stator current components in the gridconnected DFIG.
10
Brushless doubly-fed induction generator
controlled by matrix converter for wind energy
applications
UNIVERSIDAD
DE SANTIAGO
Results
The instantaneous stator current for the control DFIG.
Brushless doubly-fed induction generator
controlled by matrix converter for wind energy
applications
UNIVERSIDAD
DE SANTIAGO
Results
This results shows the stator currents corresponding to the experimental test. The gridconnected DFIG is magnetised from the control DFIG and the magnetising current of the
external loop is isg*=0.
25
Cuurrent [A]
20
15
10
5
0
-5
10
15
20
25
30
Time [s]
35
40
Isgq
Isgd
Isgqref
Isgdref
45
50
 Stator currents in the grid-connected machine.
 Stator currents in the control machine.
Brushless doubly-fed induction generator
controlled by matrix converter for wind energy
applications
UNIVERSIDAD
DE SANTIAGO
Conclusions
 Experimental results have demonstrated that the performance
obtained with a brushless DFIG is similar to that obtained with a
conventional DFIG.
 No brushes are required for the connection of both rotors in a
machine with two stators and one only rotor.
 Control system
y
strategies
g
for the operation
p
below and above
synchronous speed, including the emulation of a wind turbine
have been experimentally verified.
 The proposed topology is appropriate for variable speed wind
energy applications. The design of the control loops is simplified
considering that the power spectrum density of a typical wind
profile has most of the available energy in the low frequency
region.
ICERE 2010 CHILE
International Conference and Fair on Education, Research &
Employment in the Renewable
UNIVERSIDAD
DE SANTIAGO
Brushless
hl
d bl f d induction
doubly-fed
i d
i
generator
controlled by matrix converter for wind energy
applications
A. Muñoz
University of Santiago
Chile
A. Sureda
University of Santiago
Chile
R. Cardenas
University of Santiago
Chile
R. Peña
University of Concepción