Vector Control of Three-Phase AC Machines: System Development in the Practice

345 Pages·2008·12.29 MB·English

by  Nguyen Phung Quang Dr.

Power Systems
NguyenPhungQuangandJörg-AndreasDittrich
VectorControlofThree-PhaseACMachines
·
Nguyen Phung Quang Jörg-Andreas Dittrich
Vector Control
of Three-Phase AC
Machines
System Development in the Practice
With230Figures
Prof.Dr.NguyenPhungQuang Dr.Jörg-AndreasDittrich
HanoiUniversityofTechnology Neeserweg31
DepartmentofAutomaticControl 8048Zürich
01DaiCoVietRoad Switzerland
Hanoi [email protected]
Vietnam
[email protected]
ISBN:978-3-540-79028-0 e-ISBN:978-3-540-79029-7
PowerSystemsISSN:1612-1287
LibraryofCongressControlNumber:2008925606
Thisworkissubjecttocopyright.Allrightsarereserved,whetherthewholeorpartofthe
materialisconcerned,specificallytherightsoftranslation,reprinting,reuseofillustrations,
recitation,broadcasting,reproductiononmicrofilmorinanyotherway,andstorageindata
banks.Duplicationofthispublicationorpartsthereofispermittedonlyundertheprovisions
oftheGermanCopyrightLawofSeptember9,1965,initscurrentversion,andpermission
forusemustalwaysbeobtainedfromSpringer.Violationsareliableforprosecutionunder
theGermanCopyrightLaw.
Theuseofgeneraldescriptivenames,registerednames,trademarks,etc.inthispublication
doesnotimply,evenintheabsenceofaspecificstatement,thatsuchnamesareexemptfrom
therelevantprotectivelawsandregulationsandthereforefreeforgeneraluse.
Coverdesign:deblik,Berlin
Printedonacid-freepaper
987654321
springer.com
Dedicated to my parents, my wife and my son
NguyenPhung Quang
To my mother in grateful memory
Jörg-Andreas Dittrich
Formula symbols and abbreviations
A System matrix
B Input matrix
C Output matrix
dq Field synchronous or rotor flux orientated
coordinate system
E Sensitivity function
E, E Imaginary, real part of the sensitivity function
I R
e Vector of grid voltage
N
f General analytical vector function
f ,f,f Pulse, rotor, stator frequency
p r s
G Transfer function
G Iron loss conductance
fe
H, h Input matrix, input vector of discrete system
h General analytical vector function
i Vector of magnetizing current running through L
(cid:541) m
i Vector of magnetizing current
m
i ,i dq components of the magnetizing current
md mq
i ,i ,i Vectors of grid, transformer and filter current
N T F
i,i Vector of stator, rotor current
s r
i ,i ,i ,i dq components of the stator, rotor current
sd sq rd rq
i ,i (cid:302)(cid:533) components of the stator current
s(cid:302) s(cid:533)
i ,i ,i Stator current of phases u,v,w
su sv sw
J Torque of inertia
K Feedback matrix, state feedback matrix
Lg Lie derivation of the scalar function g(x) along the
f
trajectory f(x)
L , L, L Mutual, rotor, stator inductance
m r s
L , L d axis, q axis inductance
sd sq
L , L Rotor-side, stator-side leakage inductance
(cid:305)r (cid:305)s
m , m Motor torque, generator torque
M G
N Nonlinear coupling matrix
p Copper loss
Cu
p Total loss
v
p ,p Iron loss
v,fe Fe
VIII Formula symbols and abbreviations
R, R Two-dimensional current controller
I IN
R , R Filter resistance, inductor resistance
F D
R Iron loss resistance
fe
R, R Rotor, stator resistance
r s
Flux controller
R
(cid:90)
r Vector of relative difference orders
r Relative difference order
s Complex power
S Loss function
s Slip
T Sampling period
T Pulse period
p
T, T Rotor, stator time constant
r s
T , T d axis, q axis time constant
sd sq
t Protection time
D
t , t Turn-on, turn-off time
on off
t Transfer ratio
r
t , t , t Switching time of inverter leg IGBT’s
u v w
u Input vector
u , u , … , u Standard voltage vectors of inverter
0 1 7
U DC link voltage
DC
u Vector of grid voltage
N
u, u Vector of stator, rotor voltage
s r
u , u , u , u dq components of the stator, rotor voltage
sd sq rd rq
u , u (cid:302)(cid:533) components of the stator voltage
s(cid:302) s(cid:533)
V Pre-filter matrix
w Input vector
x State vector
x Control error or control difference
w
z State vector
z Number of pole pair
p
Z Complex resistance or impedance
s
(cid:302)(cid:533) Stator-fixed coordinate system
(cid:590) Transition or system matrix of discrete system
(cid:90) Main flux linkage
(cid:541)
(cid:90) , (cid:90), (cid:90) Vector of pole, rotor, stator flux
p r s
(cid:90)/,(cid:90)/ Vector of rotor, stator flux in terms of L
r s m
(cid:90) , (cid:90) , (cid:90) , (cid:90) dq components of the stator, rotor flux
sd sq rd rq
Formula symbols and abbreviations IX
(cid:90)/ ,(cid:90)/ ,(cid:90)/ ,(cid:90)/ Components of (cid:90)/
rd rq r(cid:66) r(cid:67) r
(cid:90)/ ,(cid:90)/ Components of (cid:90)/
sd sq s
(cid:540) Eigen value
i
(cid:88), (cid:88), (cid:88) Mechanical rotor velocity, rotor and stator circuit
r s
velocity
(cid:43), (cid:43) Rotor angle, angle of flux orientated coordinate
s
system
(cid:305) Total leakage factor
ϕ Angle between vectors of stator or grid voltage and
stator current

ADC Analog to Digital Converter
CAPCOM Capture/Compare register
DFIM Doubly-Fed Induction Machine
DSP Digital Signal Processor
DTC Direct Torque Control
EKF Extended Kalman Filter
FAT Finite Adjustment Time
GC Grid-side Converter or Front-end Converter
IE Incremental Encoder
IGBT Insulated Gate Bipolar Transistor
IM Induction Machine
KF Kalman Filter
MIMO Multi Input – Multi Output
MISO Multi Input – Single Output
MRAS Model Reference Adaptive System
NFO Natural Field Orientation
PLL Phase Locked Loop
PMSM Permanent Magnet Excited Synchronous Machine
PWM Pulse Width Modulation
SISO Single Input – Single Output
VFC Voltage to Frequency Converter
VSI Voltage Source Inverter
(cid:541)C, (cid:541)P Microcontroller, microprocessor
Table of Contents
A Basic Problems
1 Principles of vector orientation and vector 1
orientated control structures for systems
using three-phase AC machines
1.1 Formation of the space vectors and its vector orientated 1
philosophy
1.2 Basic structures with field-orientated control for three-phase 6
AC drives
1.3 Basic structures of grid voltage orientated control for 11
DFIM generators
1.4 References 15
2 Inverter control with space vector modulation 17
2.1 Principle of vector modulation 18
2.2 Calculation and output of the switching times 23
2.3 Restrictions of the procedure 26
2.3.1 Actually utilizable vector space 26
2.3.2 Synchronization between modulation and signal 28
processing
2.3.3 Consequences of the protection time and its compensation 29
2.4 Realization examples 31
2.4.1 Modulation with microcontroller SAB 80C166 33
2.4.2 Modulation with digital signal processor 37
TMS 320C20/C25
2.4.3 Modulation with double processor configuration 45
2.5 Special modulation procedures 49
2.5.1 Modulation with two legs 49
2.5.2 Synchronous modulation 51
2.5.3 Stochastic modulation 53
2.6 References 58
XII Table of Contents
3 Machine models as prerequisite to design the 61
controllers and observers
3.1 General issues of state space representation 61
3.1.1 Continuous state space representation 61
3.1.2 Discontinuous state space representation 63
3.2 Induction machine with squirrel-cage rotor (IM) 69
3.2.1 Continuous state space models of the IM in stator-fixed 70
and field-synchronous coordinate systems
3.2.2 Discrete state space models of the IM 78
3.3 Permanent magnet excited synchronous machine (PMSM) 85
3.3.1 Continuous state space model of the PMSM in the field 85
synchronous coordinate system
3.3.2 Discrete state model of the PMSM 88
3.4 Doubly-fed induction machine (DFIM) 90
3.4.1 Continuous state space model of the DFIM in the grid 90
synchronous coordinate system
3.4.2 Discrete state model of the DFIM 93
3.5 Generalized current process model for the two machine 95
types IM and PMSM
3.6 Nonlinear properties of the machine models and the way 97
to nonlinear controllers
3.6.1 Idea of the exact linearization 98
3.6.2 Nonlinearities of the IM model 100
3.6.3 Nonlinearities of the DFIM model 102
3.6.4 Nonlinearities of the PMSM model 103
3.7 References 105

4 Problems of actual-value measurement and 107
vector orientation
4.1 Acquisition of the current 108
4.2 Acquisition of the speed 110
4.3 Possibilities for sensor-less acquisition of the speed 116
4.3.1 Example for the speed sensor-less control of an IM drive 118
4.3.2 Example for the speed sensor-less control of a PMSM 125
drive
4.4 Field orientation and its problems 127
4.4.1 Principle and rotor flux estimation for IM drives 128
4.4.2 Calculation of current set points 134
4.4.3 Problems of the sampling operation of the control system 135
4.5 References 139
Table of Contents XIII
B Three-Phase AC Drives with IM and PMSM

5 Dynamic current feedback control for fast torque 143
impression in drive systems
5.1 Survey about existing current control methods 144
5.2 Environmental conditions, closed loop transfer function 155
and control approach
5.3 Design of a current vector controller with dead-beat 159
behaviour
5.3.1 Design of a current vector controller with dead-beat 159
behaviour with instantaneous value measurement of the
current actual-values
5.3.2 Design of a current vector controller with dead-beat 163
behaviour for integrating measurement of the current
actual-values
5.3.3 Design of a current vector controller with finite 165
adjustment time
5.4 Design of a current state space controller with dead-beat 167
behaviour
5.4.1 Feedback matrix K 168
5.4.2 Pre-filter matrix V 169
5.5 Treatment of the limitation of control variables 172
5.5.1 Splitting strategy at voltage limitation 174
5.5.2 Correction strategy at voltage limitation 180
5.6 References 182

6 Equivalent circuits and methods to determine 185
the system parameters
6.1 Equivalent circuits with constant parameters 186
6.1.1 Equivalent circuits of the IM 186
6.1.1.1 T equivalent circuit 186
6.1.1.2 Inverse Γ equivalent circuit 188
6.1.1.3 Γ equivalent circuit 189
6.1.2 Equivalent circuits of the PMSM 190
6.2 Modelling of the nonlinearities of the IM 191
6.2.1 Iron losses 191
6.2.2 Current and field displacement 194
6.2.3 Magnetic saturation 198
6.2.4 Transient parameters 204
6.3 Parameter estimation from name plate data 204
6.3.1 Calculation for IM with power factor cosϕ 205