1R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Central R&D at Danfoss

Operation Innovation

Claus Thybo

RA-DP

January 2006

2R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

RA Growth and Innovation Drivers

• Market Development (MD)

• Mergers and Acquisitions (M&A)

• Research and Development (R&D)

3R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Agenda

- Strategy and mission

- RA-D’ s R&D activities

- Identify future fields of interest

- The control group

- Fault detection and diagnosis

4R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

We contribute to RA´s medium and longterm development:

• Run projects on new technologies relevant for RA’s business areas.

• Maintain and renew a selection of RA´s core competencies and knowledge.

• R&D networking with customers, knowledge centres and organisations.

Central R&D Staff and ”2001 Mission”

K aren M arie M adsen

V iggo M aegaard

John D ahl

RA-D EAdm inistration/

Tech. Assistance

K laus Lam bers

U w e Lø h

M ads P eder M adsen

V erne r N eum ann

Jan P r ins

B ir the N issen R eese

C hr is t ian V e je

S t ina H akonsen A ndersen

Le if T ors ten B oysen

Jakob S pangberg

La rs O tten

RAV-CO

RA-D MCentral Com pressors R&D

Jü rge n S üß

B irg it te B rode rsen

K ars ten Len tfe r H ansen

Lars F inn S lo th La rsen

H o lge r N ico la isen

B ja rne D . R asm ussen

C laus T hybo

RA-D PCentral Controls R&D

O le P lo ug

RA-DCentral R&D

Jü rge n S üß

5R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Studies

Idea Generation

Universities

Idea

Project

Idea-pro

ject

transfo

rmer

ConceptIdea

Interactionwith BUs

Patent evaluation

Confe

r-

ence

s

Mar

ket

feed

back

RA-D Seen as a Think Tank…

6R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Concept

Idea

Secure freedom of action

Transfer to BU‘s

Support RA decision taking

Customersupport

Represent Danfoss astechnology leader

Expert-ise

Patent

Know how

… and some Outcome Examples

7R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Agenda

- Strategy and mission

- RA-D’ s R&D activities

- Identify future fields of interest

- The control group

- Fault detection and diagnosis

8R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Activity Master Plan – Stages & Interaction

BU

RA

-D

Prototyping

ProductDevelopment

MarketIntroduction

N1/N2 N5

Transfer

Star

t of

Inve

stig

atio

n

Conc

lusi

on o

f In

vest

igat

ion

Conc

lusi

on o

f Pr

otot

ypin

g

Star

t of

Tra

nsfe

r

Intr

oduc

tion

of Pr

oduc

t

Investigation

Involvement

Continuous interaction between RA-D and BUs is important

9R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Agenda

- Strategy and mission

- RA-D’ s R&D activities

- Identify future fields of interest

- The control group

- Fault detection and diagnosis

10R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Today’s Technology Development Drivers

Environmentally friendly technology

Reduction of cost

promising R&D should be ”in the middle”…

Increase of energy efficiency

11R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Agenda

- Strategy and mission

- RA-D’ s R&D activities

- Identify future fields of interest

- The control group

- Fault detection and diagnosis

12R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Scope of work - rules of the game

• Strong focus on control engineering

• We work together with international knowledge centers

• We are technology and application focused – We don’t take product responsibility!

• Our job is to make surveys of new control theory and transform promising results to prototype applications

• We try to work with scalable technology to provide technology for both low-cost and more complex products

13R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Control Engineering tasks -what we are working with

• Automated commissioning

• Fault detection and diagnosis

• Dynamic optimizing control

• Set-point optimization

14R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Agenda

- Strategy and mission

- RA-D’ s R&D activities

- Identify future fields of interest

- The control group

- Fault detection and diagnosis

15R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Fault Detection and Diagnosis in Refrigeration Systems

- A Summary of the Latest Results

Claus Thybo, M.Sc. Ph.D

Danfoss A/S

Central R&D

Refrigeration and Air-conditioning

Nordborg, Denmark

E-mail: thybo@danfoss.com

Roozbeh Izadi-Zamanabadi M.Sc. PhD

Aalborg University

Department of Control Engineering

Aalborg, Denmark

E-mail: riz@control.auc.dk

16R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Objective

•To detect and diagnose the most important faults in a typical (European) supermarket refrigeration system.

17R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

The approach•Investigate a typical European supermarket refrigeration system•Focus on the most important faults•Deriving detectors by using the analytical redundancy

The resultsDetection of … •Fan faults

•Frost build-up

•Flash-gas

•Condenser dirt build-up

•Internal compressor leakage

18R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

A Typical European Supermarket Refrigeration System

T evap in

T evap surf

T evap out

T ref out

P evap out

P amb

m air.

OD

Pexpv in

( )

( )

( , , )

air air air in air out

ref ref ref out ref in

ref expv in evap in

Q m h h

Q m h h

m f P P OD

Evaporator model

ˆ ( )

( )

air ref

air air in air out

ref ref out ref in

r Q Q

m h h

m h h

Residual

19R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

A Typical European Supermarket Refrigeration System

Condenser model( )

( )

( )

air air air in air out

ref ref ref out ref in

ref geo suc vol

Q m h h

Q m h h

m V n P

ˆ ( )

( )

air ref

air air in air out

ref ref out ref in

r Q Q

m h h

m h h

Residual

20R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Diagnosis

Cause of Fault

DetectorSymptom

Static diagnosis matrixDetector symptoms

positive

{Evaporator energybalance negative

positive

{Condenser energybalance negative

positive

{Mass-flowbalance negative Active diagnosis functionality

Attempt defrosting

Airflownormal

Airflowreduced

Fro

stbu

ild-u

p

Fan

fau

lt or

circ

ulat

ion

bloc

kage

Los

s of

air

cir

cula

tion

Los

s of

sub

cool

ing

Con

dens

er d

irty

Com

pres

sor

leak

age

21R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Conclusion

We have shown that we can detect and diagnose the most important faults in an typical European supermarket refrigeration system.

The first product with automatic fault diagnosis features was released in 2004.

We are releasing more products with fault diagnosiscapabilities as an integrated feature.

AK2 – PCIntelligent pack controllerwith fault detection

22R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

Detection of condenser dirt

Qai

r- Q

ref (

Nor

mal

ized

)

.

.

Minutes2000 2500 3000 3500 4000 4500 5000 5500 6000

0

0.5

1

23R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

550 600 650 700 750 800

0

0.5

1Detection of fan faults

Qai

r- Q

ref (

Nor

mal

ized

)

Minutes

.

.

24R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

300 350 400 450 500 550 600 650 700 750 800-1

-0.5

0

Detection of flash-gas

MinutesQai

r- Q

ref (

Nor

mal

ized

)

25R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

1000 2000 3000 4000 5000 60000

0.5

1

Detection of frost build-up

MinutesQai

r- Q

ref (

Nor

mal

ized

)

.

.

26R E F R I G E R A T I O N A N D A I R C O N D I T I O N I N G

0 100 200 300 400 500 600 700 800 900 1000

10

20

30

40

50

60

70

80

Condenser position/ normalized airflow

Tem

pera

ture

[°C

]

Cross-flow Condenser Temperature Profile

Refrigerant temperature Refrigerant flow direction

Air flow direction

Condenser surface temperature

Refrigerantgas-phase Refrigerant two-phase

Sub cooled refrigerant

Airside temperature profile