This ppt shows the modelling and simulation of permanent magnet synchronous motor by using torque control method.
And this is the most advanced and soffestigated method to control the pmsm motors.
Permanent Magnet Synchronous motor (PMSM) or Permanent Magnet AC motor:
Introduction to PMSM motor.
Types of PMSM Motor.
Mathematical modelling of PMSM motor.
Advantages and dis Advantages of PMSM motor
A permanent magnet AC (PMAC) motor is a synchronous motor, meaning that its rotor spins at the same speed as the motor's internal rotating magnetic field. Other AC synchronous technologies include hysteresis motors, larger DC-excited motors, and common reluctance motors.
(c) beta.machinedesign.com
Permanent Magnet Synchronous motor (PMSM) or Permanent Magnet AC motor:
Introduction to PMSM motor.
Types of PMSM Motor.
Mathematical modelling of PMSM motor.
Advantages and dis Advantages of PMSM motor
A permanent magnet AC (PMAC) motor is a synchronous motor, meaning that its rotor spins at the same speed as the motor's internal rotating magnetic field. Other AC synchronous technologies include hysteresis motors, larger DC-excited motors, and common reluctance motors.
(c) beta.machinedesign.com
Induction motor modelling and applicationsUmesh Dadde
A three-phase induction motor is one of the most popular and versatile motor in electrical
power system and industries. It can perform the best when operated using a balanced three-phase
supply of the correct frequency. In spite of their robustness they do occasionally fail and their
resulting unplanned downtime can prove very costly. Therefore, condition monitoring of
electrical machines has received considerable attention in recent years.
Torque Production & Control of Speed in Synchronous Motor.
Speed of synchronous motors can be controlled using two methods called open loop and close loop control.
Open loop contol is the simplest scalar control method where motor speed is controlled by independent frequency control of the converter.
In case of close loop self control mode, instead of controlling the inverter frequency independentaly, the frequency and the phase of the output waveform are controlled by an absolute position encoder mounted on the machine shaft giving an account of position of the rotor.
A synchronous motor is electrically identical with an alternator or AC generator.
A given alternator ( or synchronous machine) can be used as a motor, when driven electrically.
Some characteristic features of a synchronous motor are as follows:
1. It runs either at synchronous speed or not at all i.e. while running it maintains a constant speed. The only way to change its speed is to vary the supply frequency (because NS=120f/P).
2. It is not inherently self-starting. It has to be run up to synchronous (or near synchronous) speed by some means, before it can be synchronized to the supply.
3. It is capable of being operated under a wide range of power factors, both lagging and leading. Hence, it can be used for power correction purposes, in addition to supplying torque to drive loads.
Study of Permanent Magnent Synchronous MacnineRajeev Kumar
With respect of designing a PMSG, the permanent magnetic pole lies on the rotor and armature winding are in the inner part of stator that is electrically connected to the load. Armature winding consists of the set of three conductors which has phase difference 120 derg apart to each other and providing a uniform force or torque on the generator’s rotor. To operate PMGS, it is connected to wind turbine through a shaft without gear box and rotate at slow speed. This uniform torque produced by the resultant magnetic flux which induces current in the armature winding. The stator magnetic field combined spatially with rotor magnetic flux and rotates as the same speed of the rotor. So the two magnetic fields synchronously rotate in PGSM to maintain the relative motion of rotor and stator.
Thus the permanent magnets rotates at constant speed without any DC excitation system, which means it has not required any slip rings and contact brushes to make it more reliability or efficient.
In recent years, Permanent Magnet Synchronous Machines (PMSMs) are increasing
applied in several areas such as generation, traction, automobiles, robotics and aerospace
technology. Basically PMSG topology has been beneficial for slow speed and variable speed
operation and steady state output power produced in operation. PMSG is a part of
synchronous machine family, so its construction features almost equivalent to synchronous
machine.
With respect of designing a PMSG, the permanent magnetic pole lies on the rotor and
armature winding are in the inner part of stator that is electrically connected to the load.
Armature winding consists of the set of three conductors which has phase difference 1200
apart to each other and providing a uniform force or torque on the generator’s rotor. To
operate PMGS, it is connected to wind turbine through a shaft without gear box and rotate at
slow speed. This uniform torque produced by the resultant magnetic flux which induces
current in the armature winding. The stator magnetic field combined spatially with rotor
magnetic flux and rotates as the same speed of the rotor. So the two magnetic fields
synchronously rotate in PGSM to maintain the relative motion of rotor and stator.
Thus the permanent magnets rotates at constant speed without any DC excitation system,
which means it has not required any slip rings and contact brushes to make it more reliability
or efficient.
Induction motor modelling and applicationsUmesh Dadde
A three-phase induction motor is one of the most popular and versatile motor in electrical
power system and industries. It can perform the best when operated using a balanced three-phase
supply of the correct frequency. In spite of their robustness they do occasionally fail and their
resulting unplanned downtime can prove very costly. Therefore, condition monitoring of
electrical machines has received considerable attention in recent years.
Torque Production & Control of Speed in Synchronous Motor.
Speed of synchronous motors can be controlled using two methods called open loop and close loop control.
Open loop contol is the simplest scalar control method where motor speed is controlled by independent frequency control of the converter.
In case of close loop self control mode, instead of controlling the inverter frequency independentaly, the frequency and the phase of the output waveform are controlled by an absolute position encoder mounted on the machine shaft giving an account of position of the rotor.
A synchronous motor is electrically identical with an alternator or AC generator.
A given alternator ( or synchronous machine) can be used as a motor, when driven electrically.
Some characteristic features of a synchronous motor are as follows:
1. It runs either at synchronous speed or not at all i.e. while running it maintains a constant speed. The only way to change its speed is to vary the supply frequency (because NS=120f/P).
2. It is not inherently self-starting. It has to be run up to synchronous (or near synchronous) speed by some means, before it can be synchronized to the supply.
3. It is capable of being operated under a wide range of power factors, both lagging and leading. Hence, it can be used for power correction purposes, in addition to supplying torque to drive loads.
Study of Permanent Magnent Synchronous MacnineRajeev Kumar
With respect of designing a PMSG, the permanent magnetic pole lies on the rotor and armature winding are in the inner part of stator that is electrically connected to the load. Armature winding consists of the set of three conductors which has phase difference 120 derg apart to each other and providing a uniform force or torque on the generator’s rotor. To operate PMGS, it is connected to wind turbine through a shaft without gear box and rotate at slow speed. This uniform torque produced by the resultant magnetic flux which induces current in the armature winding. The stator magnetic field combined spatially with rotor magnetic flux and rotates as the same speed of the rotor. So the two magnetic fields synchronously rotate in PGSM to maintain the relative motion of rotor and stator.
Thus the permanent magnets rotates at constant speed without any DC excitation system, which means it has not required any slip rings and contact brushes to make it more reliability or efficient.
In recent years, Permanent Magnet Synchronous Machines (PMSMs) are increasing
applied in several areas such as generation, traction, automobiles, robotics and aerospace
technology. Basically PMSG topology has been beneficial for slow speed and variable speed
operation and steady state output power produced in operation. PMSG is a part of
synchronous machine family, so its construction features almost equivalent to synchronous
machine.
With respect of designing a PMSG, the permanent magnetic pole lies on the rotor and
armature winding are in the inner part of stator that is electrically connected to the load.
Armature winding consists of the set of three conductors which has phase difference 1200
apart to each other and providing a uniform force or torque on the generator’s rotor. To
operate PMGS, it is connected to wind turbine through a shaft without gear box and rotate at
slow speed. This uniform torque produced by the resultant magnetic flux which induces
current in the armature winding. The stator magnetic field combined spatially with rotor
magnetic flux and rotates as the same speed of the rotor. So the two magnetic fields
synchronously rotate in PGSM to maintain the relative motion of rotor and stator.
Thus the permanent magnets rotates at constant speed without any DC excitation system,
which means it has not required any slip rings and contact brushes to make it more reliability
or efficient.
MODELLING AND IMPLEMENTATION OF AN IMPROVED DSVM SCHEME FOR PMSM DTCpaperpublications3
Abstract: A very widely used drive strategy for PMSM is the field oriented control (FOC), which was proposed in 1971 for induction motors (IMs). However, the FOC scheme is quite complex due to the reference frame transformation and its high dependence upon the motor parameters and speed. To mitigate these problems, a new control strategy for the torque control of induction motor was developed by Takahashi known as the direct torque control (DTC) and by Depenbrock as the direct self control (DSC). The basic direct torque control (DTC) scheme may cause undesired torque, flux and current ripples because of the small number of applicable voltage vectors. The control system should be able to generate any voltage vector, implying the use of space vector modulation (SVM) which complicates the control scheme. The discrete space vector modulation (DSVM) method was proposed for DTC to overcome this problem which replaces the simple switching table by several switching tables, to apply a combination of three voltage vectors in the same sampling period. In this paper, after a brief review of the primary concept of DSVM DTC technique, a new scheme of DSVM DTC for PMSM is proposed with a new set of switching tables taking into account the motor speed and the absolute values of torque and flux feedback errors. In one fixed sampling time interval, three vectors are applied to the motor including the two null vectors. Comparisons of the basic DTC and the improved DSVM DTC schemes are made based on the system performance and switching loss. For this purpose the DSVM technique uses prefixed time intervals within a sampling cycle to synthesize a higher number of voltage vectors than the basic DTC scheme. A set of switching table is carried out to minimize the torque error. An optimal vector selector is developed to reduce the switching loss and make the system more stable. The sampling period does not need to be doubled in order to achieve a mean switching frequency practically equal to that of the basic DTC scheme. For a comparable performance, the switching loss of the proposed scheme is less than that of the basic DTC method. The vector application sequence is investigated and an optimal algorithm is developed to reduce the switching loss and torque ripple. Simulation and experiments on the improved DSVM DTC are carried out and compared with those on the basic DTC scheme.
Simulation of Direct Torque Control of Induction motor using Space Vector Mo...IJMER
This paper presents simulation of Direct Torque Control (DTC) of Induction Motor using Space
Vector Modulation (SVM). Direct Torque Control is a control strategy used for high performance torque
control of Induction Motor. This SVM based DTC technique reduces torque ripple and improves torque
response. The performance is explained using simulation in MATLAB environment. Result of the
simulation done in the paper shows improvement in flux and torque. These results verifies the merits of
DTC- SVM over conventional Direct Torque Control technique.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Fuzzy logic Control & Minimizing Commutation Torque Ripple for Brushless DC M...Editor IJMTER
Brushless dc motor still suffers from commutation torque ripple, which mainly depends
on speed and transient line current in the commutation interval. This paper presents a novel circuit
topology and a dc link voltage control strategy to keep incoming and outgoing phase currents
changing at the same rate during commutation. A dc–dc single-ended primary inductor converter
(SEPIC) and a switch selection circuit are employed in front of the inverter. The desired
commutation voltage is accomplished by the SEPIC converter. The dc link voltage control strategy is
carried out by the switch selection circuit to separate two procedures, adjusting the SEPIC converter
and regulating speed. The cause of commutation ripple is analyzed, and the way to obtain the desired
dc link voltage is introduced in detail. Finally, simulation and experimental results show that,
compared with the dc–dc converter, the proposed method can obtain the desired voltage much faster
and minimize commutation torque ripple more efficiently at both high and low speeds and the closed
loop control is achieved by Fuzzy logic control.
Performance Analysis of Current Controlled Three Phase Switched Reluctance Motoridescitation
Switched Reluctance Motor is an old member of Electrical Machines Family.It’s
simple structures and ruggedness and inexpensive manufacturing capability make it more
attractive for industrial application. However these merits are overshadowed by inherent
high torque ripple, acoustic noise and difficulty to control. In proposed converter, the
hysteresis
current control technique is applied
for analysis of three phase 6/4
Switched Reluctance motor. Using this technique ,torque, current, and flux linkage speed
curves of SRM are obtained at no load and load condition by MATLAB /SIMULINK.
Index Terms—
IOSR Journal of Electrical and Electronics Engineering(IOSR-JEEE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of electrical and electronics engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in electrical and electronics engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Direct torque control of IM using PID controller IJECEIAES
Direct torque control "DTC" technique is one of a high performance control system of an AC motor drive, which was proposed after the vector oriented control scheme during the resent 25 years. It has been developed rapidly for its concise system scheme, transient and dynamic performance. The DTC mechanism consists of voltage vector selection table, two hysteresis comparators and two estimator’s one for stator flux and another for electromagnetic torque. DTC is directly control torque and flux by using Voltage Source Inverter VSI, space vector and stator flux orientation and indirect speed regulated. A several control techniques can be used for improving the torque and flux performance. In this paper, the DTC with Proportional-Integral-Derivative (PID) controller used to improve the starting and dynamic performance of asynchronous motor AM, which gives good torque and flux response, best speed control and also minimize the unacceptable torque ripple. The mathematical model of DTC with PID controller of 3-phase induction motor IM are simulated under MatlabSimulink. Therefore, the DTC based on PID controller has good performance of IM compared to classical DTC for starting, running state and also during change in load.
International Refereed Journal of Engineering and Science (IRJES)irjes
a leading international journal for publication of new ideas, the state of the art research results and fundamental advances in all aspects of Engineering and Science. IRJES is a open access, peer reviewed international journal with a primary objective to provide the academic community and industry for the submission of half of original research and applications.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
A NEW FUZZY LOGIC BASED SPACE VECTOR MODULATION APPROACH ON DIRECT TORQUE CON...csandit
The induction motors are indispensable motor types for industrial applications due to its wellknown
advantages. Therefore, many kind of control scheme are proposed for induction motors
over the past years and direct torque control has gained great importance inside of them due to
fast dynamic torque response behavior and simple control structure. This paper suggests a new
approach on the direct torque controlled induction motors, Fuzzy logic based space vector
modulation, to overcome disadvantages of conventional direct torque control like high torque
ripple. In the proposed approach, optimum switching states are calculated by fuzzy logic
controller and applied by space vector pulse width modulator to voltage source inverter. In
order to test and compare the proposed DTC scheme with conventional DTC scheme
simulations, in Matlab/Simulink, have been carried out in different speed and load conditions.
The simulation results showed that a significant improvement in the dynamic torque and speed
responses when compared to the conventional DTC scheme.
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Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
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Participants will gain insights into the responsibilities, challenges, and best practices associated with test management in SAP projects. Additionally, the webinar delves into the significance of heatmaps as a visual aid for identifying testing priorities, areas of risk, and resource allocation within SAP landscapes. Through this session, attendees can expect to enhance their understanding of test management principles while learning practical approaches to optimize testing processes in SAP environments using heatmap visualization techniques
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2. Abstract
» The use of Permanent Magnet Synchronous Motors (PMSM)
combined with Direct Torque Control (DTC) scheme offers
many opportunities to achieve rapid and accurate torque
control in servo applications.
» The DTC is implemented by selecting the proper voltage
vector according to the switching status of inverter which
was determined by the error signals of reference flux linkage
and torque with their measured real values.
» Here, model of Interior type of PMSM is studied. Its
performance for various motor parameters is tested on
MATLAB-SIMULINK.
3. » DTC was proposed by TAKAHASHI and NOGUCHI in
1986 for application in Induction Motors. Their idea
was to control the stator flux linkage and the torque
directly, not via controlling the stator current.
» This was accomplished by “ OPTIMUM SWITCHING
TABLE”.
» M. F. RAH MAN investigation of direct torque control
(DTC) for PMSM drives.
» It was mathematically proven that the increase of
electromagnetic torque in a PMSM is proportional to
load angle.
Literature Review
4. » Control of the amplitude and rotating speed of the stator
flux linkage are analyzed.
» Torque response with DTC was found to be 7 times faster
than with PWM current control.
» JAWAD FAIZ introduced a new analytical technique for
generating the reference flux from the torque. It is shown
how the maximum torque per ampere (MTPA) can be
followed in the control process.
» Salient-pole PMSM motor is simulated using the
maximum torque per flux (MTPF) and the reference flux
determined.
5. » In Permanent magnet synchronous motors the
rotor winding are replaced by permanent
magnets.
» A permanent magnet synchronous machine is
basically ordinary AC machine with winding
distributed in the stator slots so that the flux
created by stator current is approximately
sinusoidal.
» Permanent magnet drives are replacing classic DC
and induction machine drives in a variety of
industrial applications such as industrial robots
and machine tools.
Introduction to PMSM
6. » Two types of permanent magnet ac motor drives are
available :
1) PMSM drive with a sinusoidal flux distribution.
2) Brushless dc motor drive with a trapezoidal flux
distribution.
Xq>Xd
There are two major topologies of rotors of PMSMs
7. » The modeling of PM motor drive system is required for
proper simulation of the system.
» The d-q model has been developed on rotor reference
frame as shown in figure:
δ
Modelling of PMSM
8. Stator and Rotor flux linkages in different frames
» The model of PMSM without damper winding has been
developed on rotor reference frame using the following
assumptions:
» Saturation is neglected.
» The induced EMF is sinusoidal
» Eddy currents and hysteresis losses are negligible.
» There are no field current dynamics.
9. » The angle between the stator and rotor flux linkage δ is the
load angle when the stator resistance is neglected.
» In the steady state, δ is constant corresponding to a load
torque and both stator and rotor flux rotate at
synchronous speed
» In transient operation δ varies and the stator and rotor flux
rotate at different speeds.
» Since the electrical time constant is normally much
smaller than the mechanical time constant, the rotating
speed of the stator flux with respect to the rotor flux can
be easily changed
10. » Voltage equations in rotor reference frame are given by
» The flux Linkages are given by
» Substituting the flux linkages in the above voltage equations
» Arranging above equations in matrix form
qdrqqq iRV
Motor Equations
dqrddd iRV
qqq iL
fmddd LiL
qqfddrqsq iLiLiRV )(
)( fddqqrdsd iLiLiRV
f
fr
d
q
dsqr
drqs
d
q
i
i
LRL
LLR
V
V
11. » The developed motor torque is being given by
» Substitution of the flux linkages in terms of the inductances and current
yields
» The mechanical torque equation is
» The rotor mechanical speed is given by
» id and iq in terms of Im
» The electromagnetic torque equation is given by
dqqde ii
p
T
22
3
dqqdqfe iiLLiPT )(
2
3
dt
d
JBTT m
mLe
dt
J
BTT mLe
m
cos
sin
m
d
q
I
i
i
sinI2sinILL
2
1
2
p
2
3
T mf
2
mqde
12. » V/F control is among the simplest control. The control is an
open-loop and does not use any feedback loops.
» The idea is to keep stator flux constant at rated value so
that the motor develops rated torque/ampere ratio over its
entire speed range.
CONTROL SCHEMES FOR PMSM
Variable Frequency Control
Vector Control
FOC DTC
Scalar Control
V/F Control
14. There are 3 signals which affect the control
action in a DTC system;
» Torque –
» The amplitude of the Stator Flux linkage –
» The angle of the resultant flux linkage vector –
(angle between stator flux vector and rotor flux
vector)
15.
16. » The stator flux linkage of PMSM is
» Neglecting the stator resistance, the stator flux
linkage can be directly defined as
dtRiV sss )(
0 stsss dtiRtV
0 stss tV
Amplitude Control of Stator Flux
Linkage (Ψs)
17. 0 stss tV 0 stss tV
HB- hysteresis-band width
20. » For counter-clockwise operation,
» if the actual torque is smaller than the reference, the
voltage vector that keeps Ψs rotation in the same direction
is selected.
» Once the actual torque is greater than the reference, the
voltage vectors that keep Ψs rotation in the reverse
direction are selected
» By selecting the voltage vectors in this way, the stator flux
linkage is rotated all the time and its rotational direction is
determined by the output of the hysteresis controller for
the torque.
The control of the rotation of stator
flux linkage
21. If the actual flux linkage is smaller than the
reference flux value then Ø = 1.
The same is true for the torque.
Working principle of Direct Torque
Control for PMSM
22. » When an upper transistor is switched on, i.e., when a, b or
c is “1”, the corresponding lower transistor is switched
off, i.e., the corresponding a’, b’ and c’ will be “0”.
VOLTAGE SOURCE INVERTER
23. switching voltage vectors
STATE Sa Sb Sc
V0 OFF OFF OFF
V1 ON OFF OFF
V2 ON ON OFF
V3 OFF ON OFF
V4 OFF ON ON
V5 OFF OFF ON
V6 ON OFF ON
V7 ON ON ON
24. » There are eight possible combinations of on and off patterns for
the upper power switches and lower power devices.
» STATE 1: ( 000 ) STATE 2: ( 100 )
» STATE 3: ( 110 ) STATE 4: ( 010 )
0,0,0 00 coba VVV
0V,VV,VV codc0bdc0a
0V,0V,VV co0bdc0a
0,,0 00 codcba VVVV
25. dccodc0b0a VV,VV,0V dcco0b0a VV,0V,0V
dcco0bdc0a VV,0V,VV dccodc0bdc0a VV,VV,VV
» STATE 5: ( 011 ) STATE 6: ( 001 )
» STATE 7: ( 101 ) STATE 8: ( 111 )
26. Vao = Vdc ; Vbo = Vdc ; Vco = 0
The space vector is Vs = Vao + Vbo ej2/3 + Vco e-j2/3
Substituting the values of Vao, Vbo and Vco:
Vs = Vdc(1/2 + j 3/2) (in rectangular form)
= Vdc 600 (in polar form)
Similarly the switching vectors can be computed for the
rest of the inverter switching states.
Computation of Switching vectors
For state-2 (+ + -):
27. Different switching states & corresponding space
vectors.
Switching state
[a b c]
Space Vector Vs
Rectangular form Polar form
V0 = [0 0 0] Vdc (0 + j0) 0 0
V1 = [1 0 0] Vdc (1 + j0) Vs 0
V2 = [1 1 0] Vdc (0.5 + j ) Vs 60
V3 = [0 1 0] Vdc (-0.5 + j ) Vs 120
V4 = [0 1 1] Vdc (-1 + j0) Vs 180
V5 = [0 0 1] Vdc (-0.5 – j ) Vs 240
29. » The three-phase variables are transformed into d-q
axes variables with the following transformation
dtirv dsdd )( dtirv qsqq )(
)( 22
qds
)(
2
3
dqqde iipT
Flux and Torque Estimator
30. Trajectory of stator flux vector in DTC
control
Inverter voltage vectors and corresponding
stator flux variation in time Δt
It receives the input signals Ф, τ θ and generates the
appropriate control voltage vector (switching states Sa, Sb, Sc)
for the inverter
Switching Table
36. 1. Simulink model
of the controller
2. Sub block of the
direct torque control
switching.
37. 1.
2.
Study of effect of magnet strength and change in M.I on
PMSM under no load and full load
Electromagnetic torque (1) and speed (2) for Ipm = 1.4 A under noload:
46. Induction torque with varying the Ipm values
Reluctance torque with varying the Ipm values
47. Study of effect of Ipm, change in M.I on PMSM with DTC for torques
48. » DTC strategy realizes almost ripple-free operation for the
electromagnetic torque and speed under no-load as well
as full-load for different values of Ipm and M.I.
» When magnetic strength value (Ipm) increases from 1.4 to
2.2, excitation torque and reluctance torque are increased
and induction torque remains unchanged.
» With the increase in moment of Inertia the response time
of drive without DTC is more, and with DTC, the drive has
smooth synchronization process.
» The simulation results verify the proposed control and also
shown that the transient response of torque and speed of
drive with DTC is much faster than the drive without DTC
Results and Conclusions