IEEE Houston Section
C ti i
Continuing
Education
Ed
ti On
O Demand
D
d
Seminar
Presentation Code: 620
April 3-4, 2007
Motor Starting
Equivalent Circuits, Starter Types, Load
Types, and Dynamics
Review of induction and synchronous motor design,
equivalent circuits for start and operation; starting,
operating and breaking operating characteristics, load
types. Review starting techniques, calculations, and
comparison.
Agenda






Induction Motor
Synchronous
y
Motor
Mechanical Train System
g, Operation
p
and Breaking
g Methods
Starting,
Special Consideration
Calculations, Simulation, Applications
Agenda
Induction Motor
 Basics, characteristics, and modeling
Synchronous Motor
 Basics, characteristics, and modeling
M h i lT
Mechanical
Train
i S
System
t




Load characteristics
Inertia
Torque Consideration
Train Acceleration Time
St ti
Starting,
Operation
O
ti and
d Breaking
B ki Methods
M th d
 Induction and Synchronous Motor
 Synchronous
y
Motor Only
y
Agenda
Special Consideration
 Harmonic Torques
 Harmonic
H
i Fl
Flux
 Rotor Slots Design
Calculations Simulation
Calculations,
Simulation, Applications
 Software
 Methodology
Induction Motor
Induction Motor

Basics, type characteristics, load
characteristics, and modeling
•
•
•
•
•
•
Induction motor - General data, principle of
operation and nameplate information describing
motor
Motor types and characteristics, application
consideration
Load types and characteristics, application
consideration
Motor model
Equivalent motor parameters
Other consideration
Induction Motor
Induction Motor

General-Non-linear Model
Induction Motor

Clark’s Transform
Induction Motor

Steady State
Us=const
Induction Motor
Induction Motor
Induction Motor
Induction Motor
Induction Motor
General data
 Motor electro-mechanical characteristics are described
by:
•
•
•
•
•
•
•
•
•
Nominal Voltage
Nominal frequency
Nominal Current
Number of phases
Number of poles
Design class
Code letter
M
Moment
off inertia
i
i
All others (rated power factor, efficiency, excitation current etc.)
Induction Motor
General data
Induction Motor
General data
Induction Motor
Type of Torques
BreakDown/Critical
Torque
Current Curve
Motor Torque Curve
Pull-up Torque
Locked Rotor/
Breakaway
Torque
Full Load
Operating
Current
Full Load
p
g
Operating
Torque
Load Torque Curve
Critical
Speed/Slip
Full Load
Operating
Speed/Slip
Induction Motor
Type of Torques
 Locked Rotor or Starting or Breakaway Torque
•
•
The Locked Rotor Torque or Starting Torque is the torque the electrical motor develop when its starts at rest
or zero speed.
A high Starting Torque is more important for application or machines hard to start - as positive displacement
pumps, cranes etc. A lower Starting Torque can be accepted in applications as centrifugal fans or pumps
where the start load is low or close to zero.
 Pull-up Torque
•
•
•
The Pull-up Torque is the minimum torque developed by the electrical motor when it runs from zero to fullload speed (before it reaches the break-down torque point)
When the motor starts and begins to accelerate the torque in general decrease until it reach a low point at a
certain speed - the pull-up torque - before the torque increases until it reach the highest torque at a higher
speed - the break-down torque - point.
The pull-up torque may be critical for applications that needs power to go through some temporary barriers
achieving
hi i the
h working
ki conditions.
di i
 Break-down Torque
•
The Break-down Torque is the highest torque available before the torque decreases when the machine
continues to accelerate to the working conditions.
 Full-load Torque or Braking Torque
•
The Full-load Torque is the torque required to produce the rated power of the electrical motor at full-load
speed.
Induction Motor
Code letters
Induction Motor
Code letters
• In general it is accepted that small motors requires higher
starting KVA than larger motors
motors. Standard 3 phase motors often
have these locked rotor codes:
o less than 1 hp: Locked Rotor Code L, 9.0-9.99 KVA
o 1 1/2 to 2 hp: Locked Rotor Code L or M
M, 9
9.0-11.19
0 11 19
o 3 hp : Locked Rotor Code K, 8.0-8.99
o 5 hp : Locked Rotor Code J, 7.1-7.99
o 7.5 to 10 hp : Locked Rotor Code H, 6.3-7.09
o more than 15 hp : Locked Rotor Code G, 5.6-6.29
Induction Motor
 Design Type
Different motors of the same
nominal horsepower can have
varying starting current
current, torque
curves, speeds, and other
variables. Selection of a particular
motor for an intended task must
take all engineering parameters
i t account.
into
t
The four NEMA designs have
unique speed-torque-slip
relationships making them suitable
to different type of applications:
• NEMA design A
• NEMA design B
• NEMA design C
• NEMA design D
Induction Motor
Design Type
• NEMA design A
o
o
o
o
o
o
maximum 5% slip
high to medium starting current
normal starting torque (150-170% of rated)
normal locked rotor torque
high breakdown torque
suited for a broad variety of applications - as fans and pumps
• NEMA design B
o
o
o
o
o
maximum 5% slip
low starting current
high locked rotor torque
normal breakdown torque
suited for a broad variety of applications, normal starting torque common in HVAC application with fans, blowers and pumps
Induction Motor
Design Type
• NEMA design C
o
o
o
o
o
o
maximum 5% slip
low starting current
high locked rotor torque
normal breakdown torque
can’t sustain overload as design A or B
suited for equipment with high inertia starts - as positive
displacement pumps
• NEMA design D
o
o
o
o
o
maximum 5-13% slip
low starting
g current
very high locked rotor torque
Usually special order
suited for equipment with very high inertia starts - as cranes, hoists
etc.
Induction Motor
Induction Motor
Ref: Donner at al. “Motor Primer”, Industry Application Transaction
Induction Motor
Ref: GE-3239A, “Comparison of IEC and NEMA/IEEE Motor Standards
Induction Motor
Torque
Induction Motor
Torque
Induction Motor
Inertia
Synchronous Motor
Synchronous Motor
Synchronous Motor

General-Non-linear Model
Synchronous Motor

Park’s Transform
Synchronous Motor

Steady State
Us=const
Synchronous Motor
Synchronous Motor
Synchronous Motor
Synchronous Motor
Synchronous Motor
High-Starting Torque
Medium-Starting Torque
Synchronous Motor
General data
 Motor electro-mechanical characteristics are described
by:
•
•
•
•
•
•
•
•
•
Nominal Voltage
Nominal frequency
Nominal Current
Number of phases
Number of poles
Design class
Code letter
M
Moment
off inertia
i
i
All others (rated power factor, efficiency, excitation current etc.)
Synchronous Motor
General data
Mechanical Train System
Load
 Load Types
TORQUE
TORQUE
SPEED
SPEED
TL( s )
TLRT  Ta n s  ( 1  s )


TL( n )
TLRT  Ta ( n )
k
1  2  3
k
k
Load
 Load Types
TORQUE
TORQUE
SPEED
SPEED
TL( n )
2
A o  B n  C n  D n
3
Load
 Load Types
TORQUE
SPEED
SPEED
Load
 ASD Application of Standard Motors
Thermal
Rating
Speed
Load
 Load Types
Application
Blowers, centrifugal:
Blowers
Valve closed
Valve open
Blowers, positive displacement, rotary, bypass
Centrifuges
Compressors, axial-vane, loaded
Compressors, reciprocating, start unloaded
Conveyors belt (loaded)
Conveyors,
Conveyors, screw (loaded)
Conveyors, shaker-type (vibrating)
Fans, centrifugal, ambient:
Valve closed
Valve open
Fans, centrifugal, hot:
Valve closed
Valve open
Fans, propeller, axial-flow
Mixers, chemical
Mixers, slurry
Pumps, adjustable-blade, vertical
Pumps, centrifugal, discharge open
Pumps oil-field,
Pumps,
oil field flywheel
Pumps, oil, lubricating
Pumps, oil, fuel
Pumps, propeller
Pumps, reciprocating, positive displacement
Pumps, screw-type, primed, discharge open
Pumps, slurry-handling, discharge open
P
Pumps,
turbine,
t bi
centrifugal,
t if
l d
deep-wellll
Pumps, vacuum (paper mill service)
Pumps, vacuum (other applications)
Pumps, vane-type positive displacement
Load Torque as a Minimum
Percent Drive Torque
Peak
Breakaway Accelerating
Running
30
40
40
40
40
100
150
175
150
50
110
40
60
100
50
130
100
150
40
100
100
125
100
100
100
100
75
25
25
60
110
50
100
25
25
40
175
150
150
40
40
40
40
40
175
150
150
50
60
40
150
60
200
110
75
125
200
150
150
150
150
100
30
100
100
100
100
60
150
100
175
100
100
100
200
150
150
150
150
100
175
100
100
100
150
100
175
Inertia
 Inertia
2
p
 ni 
 Vi 
Jz
Ji 
mi 
 

n1
n1
  i 1  
i 1
w


w - numer rotating elements
p - number
b lilinera motion
i elements
l
2
Inertia
 Inertia
2
2
2
 n1 
 n2 
 n3 
 V1 
Jz  J1  J2  J3  

J

J


J

J


m

  4 5  n   6 7  n 
1n 
 n1 
 1
 1
 1
2
Induction Motor
Torque, Speed, Inertia
Tm

  ddt nm   B nm
TL  JL  Im  


Inertia
 Torque, Speed, Inertia
Tm
TL
  JL  Im N

N
 d n   n   B  B  N2 
m L
m
  dt m 

2

N - gear ratio
J - inertia
B - dumping
Mechanical Train Acceleration
Mechanical Train Acceleration
Graphical Method
Mechanical Train Acceleration
Mechanical Train Acceleration
Mechanical Train Acceleration
Mechanical Train Acceleration
Torque Unit = S1
Speed Unit = S2
Time Unit = S3
Mechanical Train Acceleration
S1 - scale of speed acceleration
S2 - scale of torque acceleration
S3 - scale of time required to accelerate train with acceleration torque from one speed to
another
S4 - scale of dynamic energy needed for acceleration
S2
S4
S1
S3
S1
100
S2
20
S3
S4 
RPM
div1
N·m
div2
0.1sec
div3
S2 S3
S1
k
S4  0.04
2
Jtrain  0.431 kg m
OA 
 Jtrain
30 S4
2
OA  1.128m  kg
Mechanical Train Acceleration
Accelerating Energy
Unit = S4
Mechanical Train Acceleration
Mechanical Train Acceleration
Mechanical Train Acceleration
Starting Time ~ 1.5 sec
Mechanical Train Acceleration
Calculations Method
Mechanical Train Acceleration
Mechanical Train Acceleration
t
s
 n
1
ds
Ji 
  n s  
(
s
)

TL( s )
T
30

e

i
1


Mechanical Train Acceleration


t1   Js  Jm 
  n s  
30


sn
1

1
M e s  fn  U
2
  M (s )
o
ds
t 1  1.37
Mechanical Train Acceleration
In Between Method
Mechanical Train Acceleration
Mechanical Train Acceleration
48.25
43
36
35.25
28
12
tacc
RPM j
 Ji Tavg
i
j
j
Mechanical Train Acceleration
tacc  Jload 

30
 

200
28

200
35.25

200
43

200
48.25

100
36

50 

12 
tacc  1.289
Starting, Operation and Breaking Methods
Motor Starting
 Direct On Line Starter (or DOL or FVNR)
Motor Starting
 Direct On Line Starter (or DOL or FVNR)
Motor Starting
 Reduce Voltage Resistor/Reactor Starter
Motor Starting
 Reduce Voltage
Resistor/Reactor Starter
Motor Starting
 Reduce Voltage Autotransformer Starter (RVAT or
Korndörfer Starter)
Motor Starting
 Reduce Voltage Autotransformer Starter (RVAT or
Korndörfer Starter)
Motor Starting
 Reduce Voltage Autotransformer Starter (RVAT or
Korndörfer Starter)
Motor Starting
 Y / ∆ Starter
Motor Starting
 Y / ∆ Starter
Motor Starting
 Captive Transformer Starter
Motor Starting
 Wound-rotor Resistance Starter (Slip-Ring Starter)
Motor Starting
 Wound-rotor Resistance
Starter (Slip-Ring Starter)
Motor Starting
 Reduce Voltage Solid State Starter with V=var, f=const
(or RVSS)
Motor Starting
 Reduce Voltage Solid State Starter with V=var, f=const
(or RVSS)
Motor Starting
 Reduce Voltage Solid State Starter with V/f=const,
Thermal Limitation
Motor Starting
 Variable Frequency Drive Starting and Control
Motor Starting and Operating
 Variable Frequency Drive Starting and Control
Motor Starting and Operating
 Synchronous Transfer System
Synchronous Motor Starting
Synchronous Motor Starting
Synchronous Motor Starting
High-Starting Torque
Medium-Starting Torque
Synchronous Motor Starting
Starting Torque Control via
Discharge Resistor
Synchronous Motor Starting
Breaking
 Induction Machine Modes Of Operation
Break Transformer
Motor
Generator
Synchronous Speed
Breaking
 Regeneration with Active Load
Breaking
 Opposite Connection with Switching
Breaking
 Dynamic
Special Consideration
Special Consideration
 Harmonic Flux
Special Consideration
 Harmonic Torques
Special Consideration
 Typical Slot Design
Special Consideration
 Typical Slot Design
Special Consideration
 Losses and Usable Energy Separation
Stator
Rotor
Calculations, Simulation, Applications
Calculations, Simulation, Applications
Software
 ETAP, SKM/PTW
• Sufficient for DOL starting and reduce voltage discrete
calculations; not applicable for RVSS starters analysis
 SPICE, MATLAB, EMTP-ATP
EMTP ATP
• Applicable for motor starting analysis with control loops
considerations, can predict waveforms and effect on power
system
 Custom Software
• Write own software utilizing Compilers or high level language
(i M
(i.e.
Matlab
tl b or Vi
VisSim)
Si )
 Hand Calculations
• Utilize MathCad or other mathematical analysis
y
p
package;
g ; must
understand electrometrical theory
Calculations, Simulation, Applications
Equivalent Schematic Parameters – Calculations
Motor Data
Pn  1200  Hp
fn  60  Hz
Pn  895.2kW
895 2kW
Un  4kV
mkr  1.8
PFn 
 0.87
0 87
n n 
 1789  RPM
 n  0.9595
ir  5.0
mr  0.7
fs  fn
p  2
Calculations, Simulation, Applications
Equivalent Schematic Parameters – Calculations
Nominal Parameters
In 
Tn 
Pn
In  154.79A
 n  3  Un  PFn
Pn
Tn  4778.38N  m
nn
Tn  3524.36ft·lbf
30
s 
s n 
Zz 
2    fs
p
ns  nn
nn
Un
3  ir  In
n s 
60  fs
p
s  188.5s
s n  0.0061
Zz  2.98
-1
1
n s  1800RPM
Calculations, Simulation, Applications
Equivalent Schematic Parameters – Calculations
IS
RS
I 'r 
XS
I2
2
a X 'r  a X r
Io
I Fe
V1
RFe
Im
R' r
Xm
R' r
(1  S )
S
E1  aE 2
OR
R'r a 2 Rr

S
S
Calculations, Simulation, Applications
Equivalent Schematic Parameters – Calculations
Iteration starting parameters:
Rz  0.001  
Xz  0.2  
{ From motor equivalent diagram }
Given
Zz
mr  Tn
2
2
Rz  Xz
3
s
2
Rz
 Un 
2
 
 3  Rz2  Xz2

 Rz 
   Find Rz  Xz
 Xz 
Rz  0.7
Xz  2.9
Calculations, Simulation, Applications
Equivalent Schematic Parameters – Calculations
5
Rs  Rz 
Rs  0.35
10
5
Xs  Xz 
10
R'r  Rs
X'r  Xs
1  n
Pn  Pn 
Pun 
Xs  1.45
3
2
n
2
 In  Rz
Pn  37.79kW
Pun  25.22kW
Pm  0.01Pn
Pm  8.952kW
Pfen  Pn  Pun  Pm
Pfen  3.61kW
Rfe 
Ife 
Un
2
Rfe  4426.97
Pfen
Un
Ife  0.52A
3  Rfe
I0  20%  In
2
I0  30.96A
2
Im 
 I0  Ife
Xm 
Un
3  Im
Im  30.95A
30 95A
Xm  74.61
Calculations, Simulation, Applications
Equivalent Schematic Parameters – Calculations
f
Zs( f)  Rs 
Z'r( s  f) 
Zm 
fn
R'r
s
Change "f" only when analysis with VSD
 j  Xs

f
fn
 j  X'r
0.7
Rfe  Xm  j
Rfe  Xm  j
Z'r( s  f)  Zm( f)
Z( s  f)  Zs( f) 
U( f)  Un 
n ( s  f) 
Is( s  f) 
Te( s  f) 
Z'r( s  f)  Zm( f)
 f  R  f X j
fe
m
f 
fn
n

Zm( f) 
0.7
 f  R  f X j
fe
m
f 
fn
 n
f
fn
60  f
p
 (1  s )
U( f)
I'r( s  f)  Is( s  f) 
3  Z( s  f)
3 p
2  f
  II'r( s  f)
2  ReZZ'r( s  f) 
Zm( f)
Z'r( s  f)  Zm( f)
Calculations, Simulation, Applications
Equivalent Schematic Parameters – Calculations
Nominal Slip Calcs
s  0.0100
Given
Te s  fn 
  n  s  fn
s n  Find( s )
30
Pn  Pm
s n  0.0228
In  Is s n  fn
In  147.59A
Tn  Te s n  fn
Tn  4908.38N
4908 38N  m
Calculations, Simulation, Applications
Equivalent
Schematic
Parameters –
IEEE 112
Calculations, Simulation, Applications
Equivalent Schematic Parameters – Sensitivity
Calculations
Basis for ETAP Motor Estimating Calcs
Calculations, Simulation, Applications
Equivalent Schematic Parameters – Sensitivity
Calculations
EMTP ATP Group
EMTP-ATP
G
Software
S ft
Calculations, Simulation, Applications
Equivalent Schematic Parameters – Sensitivity
Calculations
EMTP ATP Group
EMTP-ATP
G
Software
S ft
Calculations, Simulation, Applications
U1
Isc 3P 150.0 MVA
Isc SLG 36.0 MVA
B1
13800 V
P
S
TR1
Size 3250.00 kVA
Pri Delta
y
Sec Wye-Ground
PriTap -2.50 %
%Z 5.7500 %
X/R 11.0
B2
4160 V
CB-001
CBL-0001
2- #4/0 MV
EPR
150.0 Meters
Ampacity 560.0 A
B3
4160 V
M1
2500.000 hp
Load Factor 1.00
X"d 0.17 pu
Calculations, Simulation, Applications
Calculations, Simulation, Applications
Calculations, Simulation, Applications
Calculations, Simulation, Applications
Calculations, Simulation, Applications
Calculations, Simulation, Applications
Calculations, Simulation, Applications
Calculations, Simulation, Applications
Calculations, Simulation, Applications
G1
8750 kVA
X"d 0.2 pu
U1
Isc 3P 150.0 MVA
Isc SLG 36.0 MVA
B1
13800 V
P
S
TR1
Size 3250.00 kVA
Pri Delta
Sec Wye
Wye-Ground
Ground
PriTap -2.50 %
%Z 5.7500 %
X/R 11.0
B2
4160 V
CB-001
CBL-0001
2- #4/0 MV
EPR
150.0 Meters
Ampacity 560.0 A
B3
4160 V
M1
2500.000 hp
Load Factor 1.00
X"d 0.17 pu
Calculations, Simulation, Applications
Calculations, Simulation, Applications
Calculations, Simulation, Applications
Calculations, Simulation, Applications
1.1
Ub 1Gen KCR
Ub_1Gen_KCR
Ub_2Gen_KCR
Ub_1Gen_DECS 1
1
Ub_2Gen_DECS
Ub_1Gen_KCR
09
Ub 2Gen KCR 0.9
Ub_2Gen_KCR
Ub_1Gen_DECS
Ub_2Gen_DECS
0.9
0.8
0
5
10
15
20
Time
2000
12
1.2
Ub [pu]
1800
1.1
1500
RPM
1000
Amp
1.0
09
0.9
09
0.9
Ub
0.8
0.7
500
0
1
Mot RPM
Mot Amp
0
10
20
Time
30
0.6
40
0.5
0
20
40
Time
60
Calculations, Simulation, Applications
1.2
Ub 1Gen KCR 1
Ub_1Gen_KCR
1
Ub_2Gen_KCR
0.9
Ub_1Gen_DECS
Ub_2Gen_DECS
0.8
Ub_1Gen_KCR
Ub 2Gen KCR
Ub_2Gen_KCR
Ub_1Gen_DECS
Ub_2Gen_DECS
0.6
0
5
10
15
20
Time
2000
1.2
Ub [pu]
1800
1.1
1500
RPM
1000
Amp
1.0
09
0.9
09
0.9
Ub
0.8
500
0
1
0.7
Mot RPM
Mot Amp
0
10
20
Time
30
06
0.6
40
0.5
0
20
40
Time
60
Calculations, Simulation, Applications
5000
P fpso 3500
Q fpso
P tlp
2000
Q tlp
p
500
1000
0
20
40
60
Time
1.2
2000
Ub_fpso [pu]
Ub_tlp [pu]
Mot RPM
Mot Amp
1500
1.1
Ub fpso
RPM
1000
Amp
Ub tlp
500
0
0
10
20
Time
30
40
1
1
0.9
0.9
0.8
0
20
40
Time
60
Calculations, Simulation, Applications
Motor Simulation
PARKs equations for this machnie:
ps
   s     r  j   s   s  vs
pr
   r     s  j   s   m   r
Te  Tr
n
J
pm


State variable assigment: x0 = s (stator) , x1 = r (rotor), x2 = m (angular speed)
 3


V



x



x

j



x

eff
0
1
0
2


   x1    x0  j     x2  x1 
f ( x  t)  

2


 x2  
M
 n Lk  Lr  Im x0  x1  k   n  

n
J


Calculations, Simulation, Applications
Motor Simulation
Coeficients for Runge-Kutta
g
((R-K)) interation 4th degree:
g


h
k1 ( x  t)
t  
2
2
k4 ( x  t) 
 h f ( x  k3 ( x  t)  t  h)
k1 ( x  t)  h f ( x  t)


k3 ( x  t)  h f  x 
k2 ( x  t)  h f  x 
k2 ( x  t)
h
t  
2
2
Final equation for R-K calcualtions:
 
 1




x i1  x i   k1 x i  i  h  2  k2 x i  i  h  2  k3 x i  i  h  k4 x i  i  h
6
 

Equations for current in stator:
 is 
 
 ir 

1  Lr M   s 


Lk  Lr  M Ls    r 






Calculations, Simulation, Applications
Motor Simulation
Conversion Park reference frame to phase domain:
 ( i)    h i
TP ( i) 
 cos   ( i)  cos   ( i)  2    cos   ( i)  4    





3
3






2 
  ( i)  2    sin  ( i)  4    



sin

(
i
)

sin






3
3




3


1
1
1


2
2
2


 isdi 
 
1
if( i)  TP ( i)   isq 
i
 
 0 
Pase currents
Calculations, Simulation, Applications
Motor Simulation
125
i
Angular Speed vs. time
100
50
0
0
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
h i
0
0.8
Torque vs. time
700
T .e
i
600
100
 400
400
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
h i
0
0.8
Average, dynamical and load torques
550
Te
i
Tc
Tr
i
50
i
450
0
20
40
60
i
80
100
120
Calculations, Simulation, Applications
Motor Simulation
Phase A, B, C Current
350
i.f ( i)
0
i.f ( i)
1
i.f ( i)
250
50
2 150
 350
350
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
h i
0
0.8
Phase A, B, C Current
350
i.f ( i)
0
i.f ( i)
1
i.f ( i)
250
50
2 150
 350
350
0
0
0.05
0.1
0.15
h i
0.2
0.25
0.3
Testing/Protection
Testing/Protection
Testing/Protection
8000
100
90
7000
80
6000
5000
70
Ground Current (A)
60
Avg Line Volt (V)
50
4000
3000
2000
0
200
400
600
800
1000
kvar Power (kvar)
T. C. Used (%)
30
Hottest Stator RTD (° C)
10
0
kW Power (kW)
40
20
1000
Avg Phase Current (A)
0
1200
Motor Load (x FLA)
Testing/Protection
8000
120
7000
100
Avg Phase Current (A)
6000
80
5000
4000
60
3000
40
2000
Avg Line Volt (V)
Current U/b (%)
kW Power (kW)
kvar Power (kvar)
Hottest Stator RTD (° C)
T. C. Used (%)
Ground Current (A)
20
1000
0
0
200
400
600
800
1000
1200
0
1400
Testing/Protection
120
10
9
100
8
7
80
6
Hottest Stator RTD (° C)
60
5
T. C. Used (%)
Motor Load (x FLA)
4
40
3
2
20
1
0
0
0
1000
2000
3000
4000
5000
6000
7000
943.59
872.77
801.95
731.13
660.31
589.49
518.66
447.84
377.02
306.2
235.38
164.56
93.73
22.91
-4000
TIME (ms)
0
Phase C Current (Amps)
-2000
-2000
-4000
-3000
-6000
-8000
TIME (ms)
2012.16
1943.43
1874.69
1805.95
1737.21
1668.47
1599.73
1530.99
1462.26
1393.52
1324.78
1256.04
2000
1187.3
1000
1118.56
4000
981.09
306.2
943.59
872.77
801.95
731.13
660.31
589.49
518.66
447.84
377.02
2005.92
1935.09
1864.27
1793.45
1722.63
1651.81
1580.99
1510.17
1439.34
1368.52
1297.7
1226.88
1156.06
1085.24
1014.41
-1000
1049.83
2000
912.35
TIME (ms)
843.61
LAST "BLOW" Phase C Current (Amps)
774.87
6000
235.38
LAST "BLOW" - Phase A Current (Amps)
706.13
3000
637.39
8000
568.66
4000
499.92
-3000
431.18
-3000
293.7
-2000
362.44
-2000
224.96
1000
93.73
1000
164.56
2000
156.22
2000
22.91
3000
87.49
Time
3000
-47.91
4000
18.75
-4000
Time
4000
-49.99
Phase A Current (Amps)
CURRENT (A
2005.92
1935.09
1864.27
1793.45
1722.63
1651.81
1580.99
1510.17
1439.34
1368.52
1297.7
1226.88
1156.06
1085.24
0
GE (V)
VOLTAG
2005.92
1935.09
1864.27
1793.45
1722.63
1651.81
1580.99
1510.17
1439.34
1368.52
1297.7
1226.88
1156.06
1085.24
943.59
872.77
801.95
731.13
660.31
589.49
518.66
447.84
377.02
306.2
235.38
164.56
93.73
22.91
-47.91
Time
CURRENT (A
1014.41
-1000
1014.41
-1000
-47.91
Time
ENT (A
CURRE
Testing/Protection
LAST "BLOW" Phase B Current (Amps)
0
Phase B Current (Amps)
-4000
TIME (ms)
LAST "BLOW" AN(AB) Voltage (V)
0
AN(AB) Voltage (V)
Testing/Protection
3.5
3
2.5
2
LINE
1.5
3.5
1
3
0.5
25
2.5
0
0
100
200
300
400
500
600
2
-0.5
Series1
1.5
Series2
1
3.5
05
0.5
3
0
2.5
-0.5
0
2
Series1
1.5
Series2
1
0.5
0
0
-0.5
100
200
300
400
500
600
100
200
300
400
500
600
Questions?
References
References
References
References
• Fitzgerald & Kingsley, Electric Machinery, McGraw-Hill, 1961
• Liwschitz-Garik, Whipple, A-C Machines, Van Nostrand, 1961
• Say, M.G., Alternating Current Machines, John Wiley & Sons, 1976
• Gray,
Gra Electrical Machines and Drive
Dri e S
Systems,
stems John Wile
Wiley & Sons,
Sons 1989
• Leonhard, Control of Electrical Drives, Spinger-Verlag, 1985
• Maxwell, James Clerk, A Treatise on Electricity and Magnetism, third edition, 1891
• IEEE Standard 519-1992 “IEEE Recommended Practices and Requirements
for Harmonic Control in Electrical Power Systems”, IEEE Press SH15453, New York, 1993
• Hammond, P. Power Factor Correction of Current Source Inverter Drives with Pump
Load 1980 IEEE/IAS Conference Record pp 520-529.
• Osman,
Osman R.,
R A Novel Medium
Medium-Voltage
Voltage drive Topology with Superior Input and
Output Power Quality, VI Seminario de Electronica de Potencia, 1996.
• Hammond, P., A New Approach to Enhance Power Quality for Medium Voltage Drives,
1995 IEEE/PCIC Conference Record pp231-235.
• Ferrier, R., McClear, P. Developments and Applications in High-Power Drives Proceedings,
Advanced Adjustable Speed Drive R&D Planning Forum, EPRI-CU-6279 NC, USA, Nov 87.
• Bin Wu, DeWinter, F. Voltage stress on induction motors in medium voltage (2300 to 6900V)
PWM GTO CSI drives,
drives PESC 95 Record.
Record 26th Annual IEEE Power Electronics Specialists
Conference
(Cat. No. 95CH35818) Part vol.2 p.1128-32 vol.2; IEEE, New York, NY, USA, 1995.