Summer Internship

Presentation at

University of the Ryukyus

Okinawa, Japan.

-Shashwat Tripathi

Junior Year

Btech(EE)

MMMUT

● Name:

Shashwat Tripathi

● Advisor:

Prof. Naomitsu URASAKI

● Faculty:

Electrical and Electronics

Engineering

● Date:

2018/05/21-2018/06/20

About

Internship

Institution

University of the

Ryukyus.Okinawa Prefecture,

Nakagami District,

Nishihara,Japan.

● Established in 1950 on the

remains of Shuri Castle

● Main Activities:

○ Education

○ Research

○ An Open University and Social

Mission etc.

● Faculties:

○ Faculty of Law and Letter

○ Faculty of Tourism Sciences and

Industrial Management

○ Faculty of Education

○ Faculty of Science

○ Faculty of Medicine

○ Faculty of Engineering

○ Faculty of Agriculture

Table of content

● Introduction

● Field of Research

○ Introduction to Drives

○ DC motor Vs AC motor

○ Application of speed control

Motor

○ Speed control : Static control v/s

Dynamic control

○ Vector Control System

○ Flux Weakening Control

○ Simulation result

○ Conclusion

● Tasks accomplished

○ Paper Reading

■ SMART GRID

■ Electrical vehicle

○ Presentation

Fields of Research

Advanced Electric Machinery

● Variable Speed Drives

○ DC motor

○ AC motor

○ Speed Control

● PMSM motor control

○ Flux Weakening control

Smart Grid

● Protection of

Transmission system.

● Integration of Solar

Energy .

Introduction To Speed Controlled Machine Drives

● Electrical machines are the most vital component in traction applications as they provide the electromechanical energy conversion.

● IMs are still less efficient than another class of AC machines the permanent magnet synchronous machines (PMSMs)

● PMSMs are a more suitable candidate for traction applications

● PMSMs can be divided into two categories based on geometrical construction:

○ the surface mounted permanent magnet synchronous machine (SPMs)

○ interior permanent magnet synchronous machine (IPMs)

Applications of Variable Speed Motors

High

efficiency

Quiet

Ride quality

High

speed

High quality

Home electric

appliances

Transport industrial machinery

Washing

machine

Electric Cars

Workshops

Dynamic Variable Speed Control V/S Static Variable Speed Control

DC motor vs. AC motor

StaticDynamic

Torque Control Frequency Control

Dynamic Control Static Control

qKi

N

S

×

qi

qi

K

K

0di

0di

• Torque is proportional q-axis current.

Vector Control System

• 3-Phase current is Expressed with help of

only 2 components.

• This allows easy designing of control

system.

-a a

-c

-b

b

c

Speedcontrolle

r

Current controlle

r

Inverter

Motor

dq

abc

Differential operator

+

- +-

+-*

0* di*

qi

di

qi

*

dv

*

qv

*

abcv

abci

Speed Control System

----

-

c

b

a

q

d

)sin()sin(sin

)cos()cos(cos

32

32

32

32

Flux Weakening Control

Fig:Current angle.

])([22

3 r

qs

r

dsqsds

r

qsfe iiLLiP

T -

Simulation without Flux Weakening

Simulation Results with Flux-Weakening.

Change in Frequency During control

ConclusionOf Flux-weakening Control

Simulation● It is very Effective when Inductance

difference between Q and D axis is high.

● Controls Torque and prevents its decline

to Zero.

● Speed of 2500rpm is possible.

Tasks

accomplishedDuring Internship Period

● Intensive Lectures on the topic Advanced Electric

Machinery attended.

● Research in the field of Interest Completed.

● The working of PMSM (Permanent Magnet

Synchronous Motor) and its control simulated on PSIM

software

● Research Papers Read:

○ A review of Flux-weakening control in Permanent Magnet

Synchronous machines

○ Optimization for Hybrid Energy Storage System in Electric

vehicles using dynamic programming approach.

○ Provide new protection system for the management of the energy

resources with regard to the use of distributed generation source in

SMART GRID

• Attended classes of Prof. URASAKI at the topic

“Theory of Electromechanical Energy Conversion”. And

presented a presentation on topic “Steady-state and

dynamicperformance of a system”.

Main Personnel Involved

Prof. Tomohiso Wada

Guidance and

Counsellor

Prof. Naomitsu Urasaki

Advisor

Shiho Oshiro san

Student Helper

Dean Arizumi Yasunori

Dean Of Faculty of

Engineering

Vote of Thanks

● I thank Prof. Tomohiso Wada for his guidance, during as well as before this Summer Internship program

,for taking care of all of us and for the delicacies at ‘THE WADAs’.

● My advisor Prof. Naomitsu Urasaki for guiding me in every nook and corner of the research work and

imparting valuable information regarding Japan.

● Dean Arizumi Yasunori for his immense support and contribution to this program

● I also thank Shiho Oshiro san and Akita Kaito san for their enormous support and Lovely Trips

● Prof. Minoru Yaga for the trips across Okinawa.

● I thank to my Lab Partners and Dormitory Mates and all my New found Friends for making this visit

memorable

● Lastly, I thank all the professors and students who were directly or indirectly involved in this summer

program for making it a successful