NSF-Sponsored Workshop on Electric Energy Research and Education

Doha, Qatar December 13-16, 2009

The University of Minnesota Experience:Sustainable Electric Energy Systems

Research and Education

Ned Mohan, University of Minnesota

mohan@umn.edu

Financial Crisis, Energy Crisis and

Climate Change700 B$/yrProduction and

Consumption

Source: DOE

Electric Power Generation by Fuel

Type:

Source: DOE

Need and Challenges in

Workforce Development

( )a ( )b( )a ( )b

0 69010 60

VHz

34.5kV

161kV

Power ElectronicsConverters

V

Time0

60 Hz

Low-VoltageRide-Through

Generator

690V

Need for an Integrated

Curriculum

UMN Undergraduate Curriculum

Core Courses

Power Electronics

Electric Drives

Power Systems

Core Courses

Power Electronics

Electric Drives

Power Systems

(a) (b)

ElectricEnergySystems

ControlSystems

ProgrammingLanguages

MecahnicalSystems

Complementary

Course

Analog and Digital Control

Communication

Digital Signal Processors

Field Programable Gate Arrays

Programming Languages

Heat Transfer, Thermodynamics

Economics and Policy Issues

Core Courses

Power Electronics

Electric Drives

Power Systems

Core Courses

Power Electronics

Electric Drives

Power Systems

(a) (b)

ElectricEnergySystems

ControlSystems

ProgrammingLanguages

MecahnicalSystems

Complementary

Course

Analog and Digital Control

Communication

Digital Signal Processors

Field Programable Gate Arrays

Programming Languages

Heat Transfer, Thermodynamics

Economics and Policy Issues

( )a ( )b

Power Electronics Course

Power Electronics Lab

FPGA Controller

( )a ( )b

PowerProcessing

Unitfixedform

Electric Source(utility)

Controller

Electric Drive

adjustableform

Sensors

input command(speed / position)

Motor

speed /position

LoadPower

ProcessingUnitfixed

formElectric Source

(utility)

Controller

Electric Drive

adjustableform

Sensors

input command(speed / position)

Motor

speed /position

Load

Electric Drives Course

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

Fig. B-6 Space vector representation of sinusoidal flux density distribution. Fig. 11 Space-vector representation in ac machines.

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

Fig. B-6 Space vector representation of sinusoidal flux density distribution.

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

Fig. B-6 Space vector representation of sinusoidal flux density distribution. Fig. 11 Space-vector representation in ac machines.Fig. 12 Space vector representation in ac machines.

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

Fig. B-6 Space vector representation of sinusoidal flux density distribution. Fig. 11 Space-vector representation in ac machines.

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

Fig. B-6 Space vector representation of sinusoidal flux density distribution.

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

Fig. B-6 Space vector representation of sinusoidal flux density distribution. Fig. 11 Space-vector representation in ac machines.

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

Fig. B-6 Space vector representation of sinusoidal flux density distribution. Fig. 11 Space-vector representation in ac machines.

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

Fig. B-6 Space vector representation of sinusoidal flux density distribution.

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

(b)

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240

axisb

axisa

axisc

ci

bi

ai

Bis

s

sii BisB B

o120

o0

o240(a) (c)

Fig. A-9 Space vector representation of sinusoidal flux density distribution.

axisa Bis

siB

0

( )si

B

axisa Bis

siB

0

( )si

B

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

ˆsI

at time tmagnetic axis of theequivalent winding

ˆwith current sI

axisa

si

si

Fig. B-6 Space vector representation of sinusoidal flux density distribution. Fig. 11 Space-vector representation in ac machines.Fig. 12 Space vector representation in ac machines.

Use of Space Vectors

- Physics-based approach

.

.

e B u

f B i

a axisstator

A axisrotor

d axis

m

isd

isq

q axisat t

i rq

ird

m

is

ir

3

2isd

3

2isq

3

2irq 3

2ird

d

d

da

dA

3

2sN

3

2sN

3

2sN

Figure 3-3 Stator and rotor mmf representation by

equivalent dq winding currents.

a axisa axisstator

A axisA axisrotor

d axisd axis

m

m

isdisd

isqisq

q axisq axisat tat t

i rqi rq

irdird

m

m

is

is

ir

ir

3

2isd

3

2isd

3

2isq

3

2isq

3

2irq

3

2irq 3

2ird

3

2ird

d

d

da

dA

3

2sN

3

2sN

3

2sN

Figure 3-3 Stator and rotor mmf representation by

equivalent dq winding currents.Figure 3-3 Stator and rotor representation by equivalent dq winding currents. The

dq winding voltages are defined as positive at the dotted terminals.

Note that the relative positions of the stator and the rotor current

space vectors are not actual, rather only for definition purposes.

a axisstator

A axisrotor

d axis

m

isd

isq

q axisat t

i rq

ird

m

is

ir

3

2isd

3

2isq

3

2irq 3

2ird

d

d

da

dA

3

2sN

3

2sN

3

2sN

Figure 3-3 Stator and rotor mmf representation by

equivalent dq winding currents.

a axisa axisstator

A axisA axisrotor

d axisd axis

m

m

isdisd

isqisq

q axisq axisat tat t

i rqi rq

irdird

m

m

is

is

ir

ir

3

2isd

3

2isd

3

2isq

3

2isq

3

2irq

3

2irq 3

2ird

3

2ird

d

d

da

dA

3

2sN

3

2sN

3

2sN

Figure 3-3 Stator and rotor mmf representation by

equivalent dq winding currents.Figure 3-3 Stator and rotor representation by equivalent dq winding currents. The

dq winding voltages are defined as positive at the dotted terminals.

Note that the relative positions of the stator and the rotor current

space vectors are not actual, rather only for definition purposes.

Mutual Inductance between dq Windings on the Stator and the Rotor

sd s sd m rdL i L i

sq s sq m rqL i L i

rd r rd m sdL i L i

rq r rq m sqL i L i

sd s sd m rdL i L i

sq s sq m rqL i L i

rd r rd m sdL i L i

rq r rq m sqL i L i

3

2s

s m s

r m r

N turns

L L L

L L L

Graduate-Level Textbook:

Drives Board for Motor and Active Load (Generator) 42 - V Motor Set

Electric Drives Lab:- Low-cost; 42-V no Shock Hazard!

- DSP Controlled; easy to use

- Active Load Allows Experiments

otherwise not possible

- Very Popular with students!

Bus-1 Bus-3

Bus-2

1mP1eP

2mP

2eP

P jQ

200km

150km150km

Power Systems Course

• Balanced Coverage of Topics

– Changing Landscape and

Resources

– Apparatus in Generation &

Delivery of Power

– Analysis and Operation

– Protection

Curriculum Developed:

Bus-1 Bus-3

Bus-2

1mP1eP

2mP

2eP

Software-based Lab:

- MATLAB/Simulink,

PowerWorld, EMTDC

- Complete Lab on CD

- 18 Short Video Clips

- Course Learning Objectives

- Online Homework Problems

Textbook- Slides

- Solutions

manual

Power Systems

Includes Topics such as

- Renewables/Storage

- HVDC, FACTS

- Voltage Stability

Teaching Machines as a subcomponent of Drive Systems

Power Processing Unit (PPU)fixed

form

measured speed/ position

speed /position

Motor

Electric Drive

Load

input command (speed / position)

Power

Signal

adjustable form

Electric Source(utility)

Sensors

Controller

Applications:

- Harnessing of Wind Energy

- Electric and Hybrid-Electric Vehicles

Textbook- Slides

- Solutions

manual

DSP-Controlled Lab

- Course Learning Objectives

- Online Homework Problems

Electric Drives

Features:

Switching Power-Pole as

the Building-Block

Includes dc-dc Converters

and dc-ac Inverters

Feedback control of

Converters

Textbook- Slides

- Solutions

manual

Hardware Lab

- Course Learning Objectives

- Online Homework Problems

Power Electronics

HiRel Systems

Duluth, Minnesota

Phone: 218-727-3115

Lab Manuals can be downloaded from:

www.ece.umn.edu/groups/power

Increasing Enrollments:• Power Systems– 90

• Power Electronics– 118

• Electric Drives- 124(Yr 2008-2009)

Applied to DOE-FOA-152:

“A Nationwide Consortium of Universities to

Revitalize Electric Power Engineering Education by

State-of-the-Art Laboratories”

82 Universities

Thank You!