Reduced Structure Inverter Fed Electric Motor Drives: an Attempt to Improve the Cost-effectiveness, the Compactness and the Reliability of Electric and Hybrid Propulsion Systems

1
Reduced Structure Inverter Fed Electric Motor
Drives an Attempt to Improve the
Cost-effectiveness, the Compactness and the
Reliability of Electric and Hybrid Propulsion
Systems
Ahmed Masmoudi

• Research Unit on Renewable Energies Electric
  Vehicles
• University of Sfax
• Sfax Engineering School
• Tunisia

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Life Cycle Protection a Universal Commitment
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Automotive Industry Flashback
Till the 60th, automotive manufacturers didnt
worry about the cost of fuel. They have never
heard of air pollution, and they have never
thought about life cycle. Ease of operation with
reduced maintenance costs meant everything back
then.
4
Air Pollution the MajorDrawback of ICE
air pollution
ICE
5
Automotive Industry New Trends
Times have changed. In recent years, clean
air mandates are driving the market to embrace
new propulsion systems in order to
substitute or to assist the ICE, resulting in
electric and hybrid vehicles.
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Series Hybrid Powertain
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Parallel Hybrid Powertrain
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Series/Parallel Hybrid Powertrain
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Electric Machine DesignNew Trends
New approach which considers that the best
machine design is the one providing the optimum
match between the machine and the associated
converter leading to the so-called converter-fed
machines.
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Electric Machine Drives Conventional SSTPI
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Reduced Structure InvertersWhat is gained?

• Lower number of the power switches and of the
  associated control boards with respect to the
  conventional SSTPI
• Improvement of the cost-effectiveness
• Decrease of the occupied volume
• Enhanced reliability thanks to the reduction of
  the luck of failures

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Outline

• Study statement
• FSTPI fed electric machine drives
• FSTPI fed BDCM drives
• FSTPI fed IM drives
• TSTPI fed electric machine drives
• TSTPI fed BDCM drives
• TSTPI fed IM drives
• Conclusion and Outlook

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Four-switch Three-phase Inverter Fed Electric
Machine Drives
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Connections of the FSTPI
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FSTPI Fed Brushless DCMotor Drives
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FSTPI Fed BDCM Drive Principle of Operation
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FSTPI Fed BDCM Principle of Operation
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FSTPI Fed BDCM Drive Principle of Operation
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FSTPI Fed BDCM Drive Principle of Operation
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FSTPI Fed BDCM Drive Principle of Operation
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FSTPI Fed BDCM Drive Principle of Operation
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FSTPI Fed BDCM Drive Linear Speed Control
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FSTPI Fed BDCM Drive Start-up
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SSTPI Fed BDCM Drive Start-up
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FSTPI Fed BDCM Drive Start-up
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SSTPI Fed BDCM Drive Start-up
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FSTPI Fed BDCM Drive Steady-state Operation
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SSTPI Fed BDCM Drive Steady-state Operation
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FSTPI Fed BDCM Drive Fuzzy Speed Control
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FSTPI Fed InductionMotor Drives
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FSTPI Fed IM DriveDirect Torque Control Scheme
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DTC of FSTPI Fed IM DriveVector Selection Table
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DTC of FSTPI Fed IM DriveVector Selection Table
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DTC of FSTPI Fed IM DriveVector Selection Table
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DTC of a FSTPI Fed IM DriveTransient Behavior
During Start-up
SSTPI
FSTPI
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DTC of a FSTPI Fed IM DriveTransient Behavior
During Start-up
SSTPI
FSTPI
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DTC of a FSTPI Fed IM DriveTransient Behavior
During Start-up
SSTPI
FSTPI
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DTC of a FSTPI Fed IM DriveTransient Behavior
During Start-up
SSTPI
FSTPI
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DTC of a FSTPI Fed IM DriveSteady-state
Features
SSTPI
FSTPI
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DTC of a FSTPI Fed IM DriveSteady-state
Features
SSTPI
FSTPI
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DTC of a FSTPI Fed IM DriveSteady-state
Features
SSTPI
FSTPI
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Three-switch Three-phase Inverter Fed Electric
Machine Drives
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Connections of the TSTPI
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TSTPI Fed Brushless DCMotor Drives
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TSTPI Fed BDCM Drive Principle of operation
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Principle of Operation
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TSTPI Fed BDCM Drive Linear Speed Control
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TSTPI Fed BDCM Drive Start-up
Electromagnetic and Load Torques
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(N.m)

16
T
em
T

14
l
12
10
8
6
4

2
0
0
0.4
0.7
1
1.3
Time (s)
SSTPI
TSTPI
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TSTPI Fed BDCM Drive Start-up
Phase Current
100
(A)
80
i

a
60

40
20
0
-20
-40
-60
-80
-100
0
0.4
0.7
1
1.3
Time (s)
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Accounting for the Equivalent Circuit of the
Battery Pack
Modified Randles Equivalent Circuit of an Ni-mH
Battery
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Accounting for the Equivalent Circuit of the
Battery Pack
Equivalent circuit of the battery pack accounted
for
Ideal battery pack
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i
(A)
a
Accounting for the Equivalent Circuit of the
Battery Pack
i
(A)
a
40
30
20
10
0
-10
-20
-30
-40
1.21
1.215
1.22
1.225
1.23
Time (s)
Ideal battery pack
Equivalent circuit of the battery pack
(c2)
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TSTPI Fed Induction Motor Drives
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TSTPI Fed IM Drive RFOC Implementation Scheme

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TSTPI Fed IM Drive Performance Under RFOC
Reference and motor speeds




SSTPI
TSTPI
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TSTPI Fed IM Drive Performance Under RFOC
Electromagnetic and load torque

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TSTPI Fed IM Drive Performance Under RFOC
The a phase current
Steady-state phase current profiles
SSTPI
TSTPI
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TSTPI Fed IM Drive Sensorless RFOC Strategy
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TSTPI Fed IM Drive Sensorless RFOC
Reference and motor speeds


2
Sensorless RFOC strategy
Conventional RFOC strategy
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TSTPI Fed IM Drive Sensorless RFOC
Speed estimation error
0.04
W
-
W
m
est
0.02
0
-0.02
-0.04
0
0.4
0.8
1.2
1.6
2
Time (s)
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Conclusion

• Improvement of the cost-effectiveness, the
  compactness and the reliability of electric and
  hybrid propulsion systems gained by the
  integration of reduced structure inverters
• Feasibility thanks to the availability of the
  battery pack
• Both FSTPI and TSTPI associated with machines
  fed by
• rectangular currents (BDCM)
• sinusoidal currents (IM)
• Almost the same performance as those achieved
  with conventional SSTPI
• Limitation of the speed range due to the
  reduction of the average DC voltage supply

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Outlook

• The development of experimental test benches for
  the sake of the validation of the predicted
  performance
• Rethought the capabilities of reduced structure
  inverters from a troubleshooting point of view in
  an attempt to solve temporarily SSTPI failures
• Solve the problem of speed limitation through a
  reconsideration of the machine design in order to
  extend the flux weakening range

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Acknowledgment

• These works were partly supported by
• Allison Transmission Division of GMs
• (ATDGM, Indiana, USA).
• Many thanks should be addressed to Dr.
• Ahmed El-Antably, staff project engineer with
  ATDGM, for the valuable discussions.

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Acknowledgment

• Full recognition needs to be given here
  
• to Prof. Abdessattar Guermazi, to Asso. Prof.
• Asma Ben Rhouma and Bassem EL Badsi, and
• to Ass. Tec. Mariem Sahbi and Mourad Masmoudi.

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Reduced Structure Inverter Fed Electric Motor
Drives an Attempt to Improve the
Cost-effectiveness, the Compactness and the
Reliability of Electric and Hybrid Propulsion
Systems
Ahmed Masmoudi

• Research Unit on Renewable Energies Electric
  Vehicles
• University of Sfax
• Sfax Engineering School
• Tunisia

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4 Switch 3 Phase Inverter Fed Brushless DC Motor
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Transverse Flux Permanent Magnet Machines
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Connections of the TSTPI
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Achievements

• 1 patent financed by Allison Transmission
  Division of GM (IN, USA)
• 6 papers in the Int. J. for Computation
  Mathematics in Electrical and Electronic
  Engineering (COMPEL)
• 2 keynote speeches in the Int. Workshop on
  Electric and Hybrid Automotive Technologies
  (WAT07, Sfax, Tunisia)
• 8 communications in conferences
• 1 in EPE03 (Toulouse, France)
• 3 in SSD05 and SSD07 (Sousse and Hammamet,
  Tunisia)
• 4 in EVER07 (Monte-Carlo, Monaco)
• Diplomas
• 1 HDR supported
• 3 PhD in progress
• 4 Masters (3 supported, 1 in progress)
• TSTPI-BDCM drive test bench under development