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International Research Journal of Engineering and Technology (IRJET)

e-ISSN: 2395 -0056

Volume: 03 Issue: 08 | Aug-2016

p-ISSN: 2395-0072

www
...
net

Analysis of Dynamic Performance of Three Phase Induction Motor
Using Matlab Simulation
Brahmananda Das
Asst
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Department of electrical engineering
Koustuv group of institutions
Bhubaneswar,Odisha,India
dasbrahmananda1972@gmail
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INTRODUCTION

Abstract This paper investigates the dynamic

This application note describes the design of a 3-phase
AC induction vector control drive
...
They are simple, rugged, inexpensive and
available at all power ratings
...
AC induction drives offer the same control
capabilities as high performance four-quadrant DC
drives
...


performance of three phase induction motor by vector
control method
...
The block diagram is
shown in figure which describes the structure of
implement vector control algorithm
...
Initially speed
reference is set at120 radian/s and torque taken as 0 nm
...
Now speed reference changes to 160 radian/s and
torque changes to 200nm and correspondence wave form
is shown
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It was originally
developed for high-performance motor application for
industrial drives
...
In vector control
method machine is control in a synchronously rotating
frame where as in sinusoidal machine variables appears
as D
...
quantities
...
e
...
C
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For vector control direct axis components
must oriented in the direction of rotor flux and
quadrature axis components must perpendicular to it
under all operating conditions
...
This develops closed loop
control system
...
C
...


Vector control, also called field-oriented control (FOC),
is a variable-frequency drive (VFD) control method
where the stator currents of a three-phase AC electric
motor are identified as two orthogonal components
that can be visualized with a vector
...
The control system of the drive calculates from
the flux and torque references given by the drive's
speed control the corresponding current component
references
...
The pulse-width
modulation of the variable-frequency drive defines
the transistor switching according to the stator voltage
references that are the output of the PI current
controllers
...
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International Research Journal of Engineering and Technology (IRJET)

e-ISSN: 2395 -0056

Volume: 03 Issue: 08 | Aug-2016

p-ISSN: 2395-0072

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net

FOC
is
used
to
control
the AC synchronous and induction motors
...
However, it is
becoming increasingly attractive for lower
performance applications as well due to FOC's motor
size,
cost
and power
consumption reduction
superiority
...
The induction motor's (d,q)
coordinate system can be superimposed to the motor's
instantaneous (a,b,c) three-phase sinusoidal system as
shown in accompanying image (phases a & b not shown for
clarity)
...

Projections associated with the (d,q) coordinate system
typically involve: Forward projection from instantaneous
currents to (a,b,c) complex stator current space vector
representation of the three-phase sinusoidal system
...
Explanation:
The Park transformation has long been widely used in the
analysis and study of synchronous and induction machines
...
Park
...
The novelty of Park's work involves his ability to
transform any related machine's linear differential
equation set from one with time varying coefficients to
another with time invariant coefficients

Forward three-to-two phase, (a,b,c)-to-( , ) projection
using
the Clarke transformation
...
Also, backward two-tothree phase, ( , )-to-(a,b,c) projection uses space vector
PWM modulator or inverse Clarke transformation and one of
the other PWM modulators
...
However, it is not uncommon for sources to use
threeto-two, (a,b,c)-to-(d,q) and inverse projection While
(d,q) coordinate system rotation can arbitrarily be set to any
speed, there are three preferred speeds or reference frames:
Stationary reference frame where (d,q) coordinate system
does not rotate; Synchronously rotating reference frame
where (d,q) coordinate system rotates at synchronous
speed; Rotor reference frame where (d,q) coordinate system
rotates at rotor speed
...
Whereas magnetic field and
torque components in DC motors can be operated relatively
simply by separately controlling the respective field and
armature currents, economical control of AC motors in
variable speed application has required development of
microprocessor-based controls with all AC drives now using
powerful DSP (digital signal processing) technology
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8 Hz compared to standstill for closed-loop
operation
...

In vector control, an AC induction is controlled under all
operating conditions like a separately excited DC motor
...
Vector control
accordingly generates a three-phase PWM motor voltage
output derived from a complex voltage vector to control a
complex current vector derived from motor's three-phase
motor
stator
current
input
through projections or rotations back and forth between the
three-phase speed and time dependent system and these
vectors' rotating reference-frame two-coordinate time
invariant system
...
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International Research Journal of Engineering and Technology (IRJET)

e-ISSN: 2395 -0056

Volume: 03 Issue: 08 | Aug-2016

p-ISSN: 2395-0072

www
...
net

forward vector control (IFOC), IFOC being more commonly
used because in closed-loop mode such drives more easily
operate throughout the speed range from zero speed to highspeed field-weakening
...
In IFOC, flux space angle feed
forward and flux magnitude signals first measure stator
currents and rotor speed for then deriving flux space angle
proper by summing the rotor angle corresponding to the
rotor speed and the calculated reference value of slip angle
corresponding to the slip frequency
...
Sensor less control
requires derivation of rotor speed information from
measured stator voltage and currents in combination with
open-loop estimators or closed-loop observers

• Using the space vector modulation, the output 3-

Figure-1 Control Hierachy
phase voltage is generated
• Transform them to the 2-phase system (α,β) using a Clarke
transformation

There are two vector control methods, direct
or feedback vector control (DFOC) and indirect or feed
forward vector control (IFOC), IFOC being more commonly
used because in closed-loop mode such drives more easily
operate throughout the speed range from zero speed to highfield-weakening
...
In IFOC, flux space angle feed forward and
flux magnitude signals first measure stator currents
and rotor speed for then deriving flux space angle proper by
summing the rotor angle corresponding to the rotor speed
and the calculated reference value of slip angle
corresponding to the slip frequency
...
Vector control method:

• Calculate the rotor flux space vector magnitude and
position angle

3
...
To perform vector control, it
is necessary to follow these steps:

• The stator current torque (isq) and flux (isd) producing
components are separately controlled

• Measure the motor quantities (phase voltages and
currents)

• The output stator voltage space vector is calculated using
the decoupling block

• Transform them to the 2-phase system (α,β) using a Clarke
transformation

• The stator voltage space vector is transformed by an
inverse Park transformation back from

• Calculate the rotor flux space vector magnitude and
position

the d-q coordinate system to the 2-phase system fixed with
the stator
...
Using space vector modulation,the output 3-phase voltage

the d-q coordinate system to the 2-phase system fixed with
the stator

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International Research Journal of Engineering and Technology (IRJET)

e-ISSN: 2395 -0056

Volume: 03 Issue: 08 | Aug-2016

p-ISSN: 2395-0072

www
...
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vector and projection of the space vector to the quadraturephase components alpha beta
...
2Forward
and
Inverse
Transformation (a,b,c to a
backwards)

Clarke
b and

Assuming that the a axis and the a axis are in the same
direction, the quadrature-phase stator currents
Isa and isb are related to the actual 3-phase stator currents
as follows:

Figure-3 Clarke Transformation
The forward Clarke transformation converts a 3-phase
system a,b,c to a 2-phase coordinate system alpha beta
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International Research Journal of Engineering and Technology (IRJET)

e-ISSN: 2395 -0056

Volume: 03 Issue: 08 | Aug-2016

p-ISSN: 2395-0072

www
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For the non-power-invariant transformation the constant k
equals k=2/3
...
If we assume , the quadrature-phase components can
be expressed utilizing only two phases of the 3-phase
system:

vector is rotating at a rate equal to the angular frequency of
the phase currents
...
We can transform these components from
the stator reference frame to the d-q reference frame
rotating at the same speed as the angular frequency of the
phase currents
...
If we consider the d-axis aligned

Ta
The inverse Clarke transformation goes back from a 2-phase
(a,b) to a 3-phase isa, isb, isc system
...


constant k=2/3, it is given by the following equations
The components isd and isq of the current space vector in dq reference frame are determined by the following equations

3
...
They are time

b
...


expressed in the same reference frame
...
The space

can directly calculate sinqField and cosqField using division
...
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coordinate system is given by the following equations:

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International Research Journal of Engineering and Technology (IRJET)

e-ISSN: 2395 -0056

Volume: 03 Issue: 08 | Aug-2016

p-ISSN: 2395-0072

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3
...
Rotor Flux Model: Knowledge of the rotor flux
space vector magnitude and position is key information for
the AC induction motor vector control
...
There are several methods for
obtaining the rotor magnetic flux space vector
...
It is calculated in the stationary
reference frame (a,b) attached to the stator
...
5 Space Vector Modulation:

in temperature, is negligible for this rotor flux model
...


The rotor flux space vector is obtained by solving the
differential equations ,which are resolved into the a and b
components
...


The standard technique of the output voltage generation
uses an inverse Clarke transformation to obtain 3-phase
values
...
Although this technique gives good results, the
space vector modulation is more straightforward (valid only
for transformation from the a,b-coordinate system)
...
They are given by combinations of the
corresponding power switches
...
There are six non-zero
vectors, U0, U60, U120, U180, U240, U300, and two zero
vectors, O000 and O111, defined in a,b coordinates
...
Each digit represents one
phase
...
A value of zero

© 2016, IRJET

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Impact Factor value: 4
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irjet
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These states, together with the resulting
instantaneous output line-to-line voltages, phase voltages
and voltage vectors
...
The SVM technique consists of several steps: 1
...
2
...
This method gives the greatest
variability of arrangement of the zero and non-zero vectors
during the PWM period
...


3
...
5 Application Description with hardware

The principle of SVM is the application of the voltage
vectors UXXX and OXXX for certain instances in such a way
that the

Intgration:
The vector control algorithm is calculated on Motorola
DSP56F80x
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The
block diagram of the ACIM control algorithm is shown in
Figure6[8], which describes the structure of the
implemented vector control algorithm (basic blocks and
control signals)
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International Research Journal of Engineering and Technology (IRJET)

e-ISSN: 2395 -0056

Volume: 03 Issue: 08 | Aug-2016

p-ISSN: 2395-0072

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• DSP56F807EVM boards

Figure -6 Hardware Integration

• ECOPTINL, In-line optisolation box, which is connected
between the host computer and the

Measured quantities:

DSP56F80xEVM

• DCBus voltage

The drive can be controlled in two different operating
modes:

• Phase currents (Phase A, Phase B, Phase C)
• Power module temperature

• In the manual operating mode, the required speed is set
by UP/DOWN push buttons and the drive is started

• Rotor speed
The faults used for drive protection:

and stopped by the RUN/ STOP swich on the EVM board

• “Overvoltage”

• In the PC remote

• “Undervoltage”

required speed is set by the PC master software bar graph
and the drive is started and stopped by the START MOTOR

• “Overcurrent”

and STOPMOTOR controls

• “Overheating”
• “Mains out of range”

© 2016, IRJET

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Impact Factor value: 4
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irjet
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Matlab Implementation:

Figure-7 Matlab
block diagram

simulink

4
...
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International Research Journal of Engineering and Technology (IRJET)

e-ISSN: 2395 -0056

Volume: 03 Issue: 08 | Aug-2016

p-ISSN: 2395-0072

www
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net

4
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3 Theta calculation

4
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5 Iabc to Dq Conversion

4
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International Research Journal of Engineering and Technology (IRJET)

e-ISSN: 2395 -0056

Volume: 03 Issue: 08 | Aug-2016

p-ISSN: 2395-0072

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4
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8 current and speed waveform

4
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International Research Journal of Engineering and Technology (IRJET)

e-ISSN: 2395 -0056

Volume: 03 Issue: 08 | Aug-2016

p-ISSN: 2395-0072

www
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5
...
From those curves I found that
when values of torque increases from 0 to 200 and speed
increases from 120 to 160 and in next step torque increases
from 200 to 400 and speed incres from 160 to 200 which is
shown in characteristics curves
...
It is
developed using traditional PI controller,hence cost
effective
...
It is very much cost effective for
industrial drives which can replace all costly dc drives
...
There is
a large future scope for this area which can be developed
using advanced controller
...


Figure-8 for speed reference 120 radian/second and
torque 0 nm
...
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International Research Journal of Engineering and Technology (IRJET)

e-ISSN: 2395 -0056

Volume: 03 Issue: 08 | Aug-2016

p-ISSN: 2395-0072

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...
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Figure-10 for speed reference 160radian/second and
torque 200nm
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International Research Journal of Engineering and Technology (IRJET)

e-ISSN: 2395 -0056

Volume: 03 Issue: 08 | Aug-2016

p-ISSN: 2395-0072

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[3]

Murray, Aengus (Sep 27, 2007)
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EDN
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Figure-12 Dynamic characterstics when speed reference
changes from 120 to 160 to 200radian/second and
torque changes from 0 to 200 to 400 nm
...
Holtz, J
...
"Sensorless control of induction motor
drives" (PDF)
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doi:10
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2002
...
Retrieved June 3, 2012
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The proposed control method
assures: Torque generating component and magnetic field –
generating component have been controlled independently
and gives
...
The transient response
will be fast and dc machine like because torque control by
does not affect the flux
...
Good stabilization of load torque for wide range
speed control
...
It

[5] Jump up to:

is developed using traditional PI controller,hence cost
effective
...
It is very much cost effective for
industrial drives which can replace all costly dc drives
...
There is
a large future scope for this area which can be developed
using advanced controller
...


[8]DSP Manual (2007)
...
Freescale
...
25, incl
...
eq
...
Retrieved May 16, 2012

Zambada, Jorge
...
Appliance Magazine
...


[6]Yano, Masao et al
...
p
...
Retrieved 18 April 2012

[7]
...
Induction Motor Modelling for Vector
Control Purposes (PDF)
...

pp
...
ISBN 951-22-5219-8

References:
[1] Zambada, Jorge (Nov 8, 2007)
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MachineDesign
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[2] Jump up^ Bose, Bimal K
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"The Past, Present,

and Future of Power Electronics"
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doi:10
...
2009
...
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