vector control of induction machines. introduction the traditional way to control the speed of...
TRANSCRIPT
![Page 1: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/1.jpg)
Vector Control of Induction Machines
dq3
2 IM 32 dq
su si
abab
![Page 2: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/2.jpg)
Introduction
• The traditional way to control the speed of induction motors is the V/Hz-control
• Low dynamic performance• In applications like servo drives and rolling
mills quick torque response is required.• Desire to replace dc drives led to vector
control• Braunschweig, Leonhard, Blaschke, Hasse,
late 70-ies
![Page 3: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/3.jpg)
What is vector control?
• Vector control implies that an ac motor is forced to behave dynamically as a dc motor by the use of feedback control.
• Always consider the stator frequency to be a variable quantity.
• Think in synchronous coordinates.
![Page 4: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/4.jpg)
Basic blocks of a vector controlled drive
dq3
2 IM 32 dq
su si
abab
![Page 5: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/5.jpg)
Addition of a block for calculation of the transformation angle
dq3
2 IM 32 dq
su si
abab
T ra n s fo rm a tio na n g le
c a lc u la tio n
rq
![Page 6: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/6.jpg)
The current is controlled in the d- and q-directions
jref ref refs sd sqi i i
magnetization
torque production
![Page 7: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/7.jpg)
Vector controller
dq3
2 IM 32 dq
su si
abab
T ra n s fo rm a tio na n g le
c a lc u la tio n
rq
C u rre n tc o n tro lle r
refsi
+-
![Page 8: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/8.jpg)
Stator and rotor of an induction machine
![Page 9: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/9.jpg)
Magnetization current from the stator
![Page 10: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/10.jpg)
The flux
![Page 11: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/11.jpg)
1
r
The rotation
![Page 12: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/12.jpg)
2
View from the rotor
![Page 13: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/13.jpg)
v
2
dl e v B
v
B
Induced voltage and current
![Page 14: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/14.jpg)
2
F
Torque production
![Page 15: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/15.jpg)
2
Ampere-turn balance
![Page 16: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/16.jpg)
Rotor flux orientation
• Difficult to find the transformation angle since the direction of the flux must be known
• Flux measurement is required• Flux sensors (and fitting) are expensive and
unreliable• Rotor position measurement does not tell the
flux position• The solution is flux estimation
![Page 17: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/17.jpg)
Rotor flux orientation using measured flux
Original method suggested by Blaschke•Requires flux sensors•Flux coordinates: aligned with the
rotor flux linkage
arctan r
r
b
a
![Page 18: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/18.jpg)
a
b
r *
jes
f s srsr
y y y
Rotor flux orientation
![Page 19: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/19.jpg)
From Chapter 4
ssu
ssi
smi
sri
j sr r
rR
sR slL rlL
mL
s
dR (stator)
d
ss sss st
u i
r
dj R (rotor)
d
ss sr
r r rt i
![Page 20: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/20.jpg)
Transformation to flux coordinates
j j j js
de j e e R e
d
ff f fss s st
u i
j j j jr
de j e j e R e
d
ff f frr r r rt
i
![Page 21: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/21.jpg)
1 s
dj R
d
ff f fss s st
u i
2 r
dj R
d
ff frr rt
i
2 1 r
The flux coordinate system is ”synchronous” only at steady-state. During transients the speed of the rotor flux and the stator voltage may differ considerably.
![Page 22: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/22.jpg)
The rotor equation (5.9)
2 r
dj R
d
ff frr rt
i
m
r r
1 L
L Lf f fr r s i i
r m r2
r r
d R L Rj
d L L
ff f frr r st
i
![Page 23: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/23.jpg)
Split into real and imaginary parts
0frq d
0d
frq
t
r m r
r r
d R L R
d L L
ff frdrd sdit
m r2
r
L R0
Lf frd sqi
![Page 24: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/24.jpg)
Rotor flux dynamics are slow
rr
r
LT
R
f frd0 m sd0ψ L i
![Page 25: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/25.jpg)
Torque control
*m
r
3 Lp Im
2 Lf fr sT i
m
r
3 Lp
2 Lf frd sqT i
mL
refref rsdi
![Page 26: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/26.jpg)
Rotor flux orientation using estimated flux
• The rotor flux vector cannot be measured, only the airgap flux.
• Flux sensors reduce the reliability• Flux sensors increase the cost• Therefore, it is better to estimate the rotor
flux.
![Page 27: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/27.jpg)
The "current model" in the stator reference frame
(Direct Field Orientation)
r
dj R
d
ss sr
r r rt i
m
r r
1 L
L Ls s sr r s i i
m
r r
ˆd L1ˆj
d T T
ss sr
r r st
i
![Page 28: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/28.jpg)
The current model
C u rren tco n tro l
C u rren tm o d e l
IMd riv e
f
fs
s
refrd
refT
fsi s
si
ssu
fsu
r
![Page 29: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/29.jpg)
The "current model" in synchronous coordinates (Indirect Field Orientation)
m r m2 2
r r
0fsqf f
rd sq frd
iL R Li
L T
2r
1 sq
sd
i
T i f f
rd0 m sd0L i
![Page 30: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/30.jpg)
Transformation angle
1 d tq
1 2r
1
Tsq
r rsd
i
i
![Page 31: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/31.jpg)
Remarks on indirect field orientation
• Does not directly involve flux estimation (superscript f dropped)
• Not ”flux coordinates” but ”synchronous coordinates”
• Since the slip relation is used instead of flux estimation, the method is called indirect field orientation
![Page 32: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/32.jpg)
Indirect field orientation based on the current model
C u rren tco n tro l
s lipre la tio n
IMd riv esy
s
s
refrd
refT
fsi s
si
ssu
fsu
r
sy
q
q
![Page 33: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/33.jpg)
Feedforward rotor flux orientation
1r
1refsq
r refsd
i
T i
•Significantly reduced noise in the transformation angle•Fast current control is assumed (ref.value=measured value)•No state feedback => completely linear
![Page 34: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/34.jpg)
The voltage model
•The current model needs accurate values of the rotor time constant and rotor speed•The trend is to remove sensors for cost and reliability reasons•Simulate the stator voltage equation instead of the rotor voltage equation
s
ˆd
d
ss sss sR
t
u i
![Page 35: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/35.jpg)
Solve for the rotor current and insert in
s ms s rL L i i
r mr r sL L i i
rs m
m
s s s sr s s s
LL L
L i i
![Page 36: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/36.jpg)
m r/L L
2m m
sr r
s s sr s s
L LL
L L
i
Multiplication by
yields
2m
s σr
LL L
L
r
m
Lˆ ˆ L
Ls s sr s s i
Solve forsr
![Page 37: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/37.jpg)
Direct field orientation using the voltage model
C u rren tco n tro l
V o ltag em o d e l
IMd riv e
f
fs
s
refrd
refT
fsi s
si
ssu
fsu
ˆ frd
![Page 38: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/38.jpg)
Stator flux orientation
1
ˆd nominal
d
sssst
u
m
r
ˆ ˆs s ss r s
LL
L i
At low frequencies the current model can be used together with:
"Direct self-control" (DSC) schemes first suggested by Depenbrock, Takahashi, and Noguchi in the 1980s.
![Page 39: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/39.jpg)
Field weakening
M a x im u mto rq u e ra n g e
F ie ld w e a k e n in g ra n g e= > R e d u c e d to rq u e
refsdi
maxr refr
![Page 40: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/40.jpg)
Current control
R L
++su se
si
![Page 41: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/41.jpg)
dL R
d
ss s s
t
iu i e
j j j jdL e e R e e
d tq q q q i u i e
j j j j jdL e jω e e R e e
d tq q q q q
i+ i u i e
dL jω R
d t
i+ i u i e
![Page 42: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/42.jpg)
d+ j
dL R Lt
iu i e
d
dd
d d q d
iL u Ri Li e
t
d
dq
q q d q
iL u Ri Li et
![Page 43: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/43.jpg)
Transfer function and block diagram of a three-phase load
( )
1
js
s L R
G
+-
( )sG
e
ui
![Page 44: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/44.jpg)
Review of methods for current control
• Hysteresis control• Stator frame PI control• Synchronous frame PI control
![Page 45: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/45.jpg)
Hysteresis control(Tolerance band control)
• Measure each line current and subtract from the reference. The result is fed to a comparator with hysteresis.
• Pulse width modulation is achieved directly by the current control
• The switching frequency is chosen by means of the width of the tolerance band.
• No tuning is required.• Very quick response
![Page 46: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/46.jpg)
Drawbacks of hysteresis control
• The switching frequency is not constant.• The actual tolerance band is twice the chosen
one.• Sometimes a series of fast switchings occur.• Suitable for analog implementation. Digital
implementation requires a very high sampling frequency.
![Page 47: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/47.jpg)
Stator frame PI control
• Two controllers: one for the real axis and one for the imaginary axis
• Cannot achieve zero steady-state error• Tracking a sinusoid means that steady-state is
never reached in a true sense• Integral action is useless except at zero
frequency
![Page 48: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/48.jpg)
Synchronous frame PI control
• In a synchronous reference frame the current is a dc quantity at steady-state.
• Zero steay state error is possible.• Coordinate transformations necessary• Easily implemented on a DSP• Usually the best choice!
![Page 49: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/49.jpg)
Design of synchronous frame PI controllers
Remove cross-coupling
j L u u i
d+ j
dL R Lt
iu i e
dL R
d t
iu i e
![Page 50: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/50.jpg)
( )1
ss L R
G
+
+
-
refi ( )sF ( )sG
( )sG
u
e
i+
-
j L
![Page 51: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/51.jpg)
Desired closed-loop system
( )ss
aa
cG
ln(9)rta
( )i
s p
kk
s F
( ) ( )( )
( ) ( )1
s ss
s s
c
F GG
F G
![Page 52: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/52.jpg)
Choice of controller parameters
-1( ) ( )
RL R L+s s s
s s s
a a aa F G
Lpk a
Rik a
![Page 53: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/53.jpg)
Speed control
• Applications: pumps and fans in the process industry, paper and steel mills, robotics and packaging, electric vehicles
• Very different dynamic requirements• Most drives have low to medium high
requirements on dynamics. These drives are considered here.
• Cascade control is sufficient
![Page 54: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/54.jpg)
Block diagram of a speed-controlled drive system
Currentcontroller refuI
irefi
Speedcontroller
Inverter
refm
m
Electricmotor
![Page 55: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/55.jpg)
The mechanical system
d
dm
e l mT T J bt
1/ J s bm
eT
lT
![Page 56: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/56.jpg)
The speed controller
• The task of the speed controller is to provide a reference value for the torque (or current) which makes the mechanical system respond to the speed reference with a specified rise time.
ln(9)rt a
![Page 57: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/57.jpg)
Block diagram with speed controller
1/ J s bm
eT
lT
Inner loopSpeed
controller
TF c refsqi
refm
1/ Tc
132
Trefmrd
r
cL
pL
![Page 58: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/58.jpg)
1refm m mF
J s b
1oF G
J s b
1o
co
GG
G s
aa
oG s
a
![Page 59: Vector Control of Induction Machines. Introduction The traditional way to control the speed of induction motors is the V/Hz-control Low dynamic performance](https://reader035.vdocuments.site/reader035/viewer/2022070407/56649e495503460f94b3bea8/html5/thumbnails/59.jpg)
Choice of controller parameters1
FJ s b s
a
PI
bF J s b J
s s
a aa
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Realistic choice of bandwidth
• Care must be taken that the bandwidth of the speed controller is not unnecessarily high.
• In fact this should be decided during the first steps in the design process of a drive system
• The bandwidth is directly connected to the current rating of the inverter.
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A change in the speed reference
qpi J a
max max mbaseC
How large steps should be foreseen?
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qp nomi I max With and
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Check if the current controlleris sufficiently fast.