2011 - Modeling & simulation of switched reluctance motor.pdf

MODELING AND SIMULATION OF THE SWITCHED RELUCTANCE MOTOR

by

RAHEELAHMEDSHATIKH

Progress Report submitted iu partial fulfilment of the requirements for the

Bachelor of Engineering (Hons) (Electrical & Electronics Engineering)

MAY2011

Universiti Teknologi PETRONAS Bandar Seri Iskandar

31750 Tronoh Perak Darul Ridzuan

© Copyright 2011

by

Raheel Ahmed Shaikh

CERTIFICATION OF APPROVAL

MODELING AND SIMULATION OF THE SWITCHED RELUCTANCE MOTOR

by

Raheel Ahmed Shaikh

A project dissertation submitted to the Electrical & Electronics Engineering Programme

Universiti Teknologi PETRONAS in partial fulfilment of the requirement for the

Bachelor of Engineering (Hons) (Electrical & Electronics Engineering)

A p p r o v ; r &

Dr. Irraivan Elamvazuthi Project supervisor

UNIVERSITI TEKNOLOGI PETRONAS TRONOH, PERAK

MAY2011

ii

CERTIFICATION OF ORIGINALITY

This project is to certify that I am responsible for the work submitted in this project, that the original work is my own except as specified in the reference and acknowledgments, and that the original work contained herein have not been undertaken or done by un specified sources or persons.

Raheel Ahmed Shaikh

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ABSTRACT

This Paper summarizes the study conducted on the techniques used and implemented to minimize the torque ripple of the Switched reluctance Motors. These motors although offering the advantages of higher speeds, reliability and phase independence, have the limitations of the torque ripple and non-linearity in the magnetic characteristics. Thus in order to have the good understanding of the Motor, it is simulated in the MA TLAB/SIMULINK environment. This paper describes details on modeling of two different configurations of Switched Reluctance Motor concentrating only on the linear model by obeying all of its characteristics. The two configurations of motors are applied with two different control techniques and the results are calculated and tabulated. Load and No load analysis are also performed to understand the behavior of motor with load. Through out the analysis, various values of turn-on and turn-off angles are selected and finally the optimum values are calculated based on the performance parameters of Average torque, speed and torque ripple. All simulations are documented through this paper including its block models and initializations performed. Finally a control technique is recommended which produces the best results with smallest torque ripple.

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ACKNOWLEDGEMENT

First of all, I would like to thank the almighty god, who gave me the discipline and courage to finish this project. Without his blessings, the project might not have been completed. I would also like to thank both my parents for their encouragements and prayers. Without their support it would have been difficult to finish this project

Next, I would like to convey my deepest appreciation towards my final year project supervisor, Dr.

Irraivan Elamvazuthi,

who has persistently and determinedly assisted me during the project.

It

would have been very arduous to complete this project without the passionate supports and guidance encouragement and advices given by him.

Thirdly, I would like to thank to Universiti Teknologi PETRONAS (UTP) and Electrical Engineering for providing us theoretical knowledge which can be applied in our Final Year Project.

Lastly, I would love to thank the people that have been giving me morale support all the way through the time I was doing the project. Thank you.

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TABLE OF CONTENTS

ABSTRACT... iv

ACKNOWLEDGEMENT . ... ... .... ... ... .... ... ... ... ... .... ... ... ... .... .... ... v

LIST OF FIGURES... viii

LIST OF TABLE... x

NOMENCLATURE & ACRONYMS... xi

CHAPTER 1: INTRODUCTION 1.1 1.2 1.3 1.4 1.5 1.6 Background of Study ... .. Stepping Motors ... . Types of Stepping Motors ... . 1.3.1 Variable Reluctance Motor ... .. 1.3.2 Permanent Magnet Motor ... . 1.3.3 Hybrid Motor ... .. Problem Statement ... . Objectives of the Stndy ... .. Scope of Study ... .. 3 4 4 5 5 7 7 8 CHAPTER 2: LITERATURE REVIEW 2.1 Previous Work Done... 9

2.2 2.1.1 Techniques &Algorithms Applied ... .. Variable Reluctance Motor ... . 10 II 2.2.1 Advantages & Disadvantages... II 2.2.2 Construction... 12

2.2.3 Operation... 12

2.2.4 Energy Conversion Principles of SRM.. ... 13

2.2.5 Basic Control Circuit... 16

2.4.6 Torque Speed Characteristics ... 17

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CHAPTER3:METHODOLOGY

3.2 3.3

3.1 3.1.1

Project Flow ... . Phases Involved in Project Completion ... . Tools & Software Required .•...

Insight into SRM ...•...•...•...

3.3.1 3.3.2 3.3.3 3.3.4 3.3.5

SRM energizing strategies ... . Two quadrant chopping convertor ...•...

Selection of Stator and Rotor Pole arcs ....

SRM modelling equations ...•..

Application Example ... . CHAPTER 4: RESULTS & DISCUSSION

4.1

4.2

Simulation of 6/4 SRM ... . 4.1.1

4.1.2 4.1.3 4.1.4

4.1.5 4.1.6 4.1.7

Voltage Pulse technique with no load ....

Simulations with varied ()on and ()off. ..

Voltage Pulse with variable load ... . Simulation of motor with j3r

*

^j3s

Varied Bon and Bo.fffor

f3r * f3s ... .

Comparison between j3r

*

^{j3s & f3r = f3s}

Hysteresis Control with no load ... . Simulation of 8/6 SRM ... .

4.2.1 Voltage Pulse technique with no load ....

4.2.2 Varied ()on and ()off for variable load ..

CHAPTER 5: CONCLUSION & RECOMMENDATIONS

5.1 Conclusion ... ..

5.2 Recommendations ... ..

REFERENCES ... ..

APPENDIX 1: PROJECT GANTT CHART ... . APPENDIX I: SIMULATION INITALIZATIONS ... .

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19

20

21

22

27 27

29

30 32

39 45 49 52 55 57 61 ^I 62 ⁱ 70'

nl

761

'

I

79'

8oj

81

Figure 1:

Figure 2:

Figure 3:

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Figure 5:

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Figure 7:

Figure 8:

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Figure 10:

Figure II:

Figure 12:

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Figure IS:

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Figure 17:

Figure 18:

Figure 19:

Figure 20:

Figure 21:

Figure 22:

Figure 23:

Figure 24:

Figure 25:

Figure 26:

Figure 27:

LIST OF FIGURES

Classification of Motors... . . . 2

Cross section of a Variable Reluctance Motor... 4

Components of Permanent Magnet Stepper Motor... 5

Hybrid Stepping Motor... .. . .. .. .. .. .. .. .. .. .. .. . .. .. .. .. .. .. .. .. .. .. ... 6

Variable Reluctance Stepper Motor... 12

Aligned Position of SRM .. .. .. .. . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. . .. .. .. .. 14

Un-aligned Position of SRM .. .. .. .. .. .. .. .. .. .. .. .. .. . .. .. .. .. .. .. .. ... 14

Rotor Switching Sequence of VRM... .. .. .. .. .. .. .. .. .. .. . I 5 VRM Control Circuit... 17

SRM torque speed characteristics... 17

Variation oflnductance and Torque of one phase... 23

Two quadrant Chopping Convertor... 27

Switching of the Two quadrants Chopping Convertor... 28

Results produced as a result of two quadrant Chopping Convertor. 29 Model of SRM available in MATLAB... 32

MATLAB blocks for the SRM simulation... 35

Converter Block... 35

Sub-converter Block .. . .. .. .. .. . .. . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. . 35

Output of the SRM... .... .. .... .... .. .... .. .... .. ... .. . .. . 36

Output of the SRM at low speeds... 37

Mechanical equation block diagram via SIMULINK... ... 38

Complete Simulation Model of 6/4 SRM .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. . 39

Phase Model of SRM... 40

Modulo pi/2 Model... . . . 41

Switch Model... . . . 41

Inductance Model... 42

Torque Model... 43

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