Intelligent Air Conditioning System

College of Engineering & Computer Science Electrical and Computer Engineering Department

ECE 581 Fuzzy Control TAKE HOME PROJECT on

INTELLIGENCE AIR CONDITIONING SYSTEM

Summer-2015Instructor-Sequare Daniel-Berhe, Ph.D.

By,PRUTHVIRAJA BHUPAL

CONTENTS HISTORY OF AIR CONDITIONING OPERATION OF AIR CONDITIONER LINGUISTIC VARIABLES

INPUT VARIABLE-USER TEMPERATURE MEMBERSHIP FUNCTIONS INPUT VARIABLE-TEMPERATURE DIFFERENCE MEMBERSHIP FUNCTIONS OUTPUT VARIABLE-FAN SPEED MEMBERSHIP FUNCTIONS OUTPUT VARIABLE-COMPRESSOR SPEED MEMBERSHIP FUNCTIONS

MAMDANI RULES FUZZY MATCHING DEGREE INFERENCE DEFUZZIFICATION TAKAGI-SUGINO METHOD REFERENCE

HISTORY OF AIR CONDITIONER

In 1902, the first modern electrical air conditioning unit was invented by Willis Carrier in Buffalo, New York. After graduating from Cornell University, Carrier found a job at the Buffalo Forge Company, then he started experimenting with air conditioning

The 2nd-century Chinese inventor Ding Huan (ft. 180)of the Han Dynasty invented a rotary fan for air conditioning, with seven wheels 3 m (9.8 ft.) in diameter and manually powered.

In Ancient Rome, water from aqueducts was circulated through the walls of certain houses to cool them.

WILLIS CARRIER

OPERATION OF AIR-CONDITIONER Air Conditioners are Heat Exchangers.

They take in warm room air, then blow it over

the cooling coils and back into the room.

Important elements of AC.

REFRIGERANT

COMPRESSOR

EVOPERATOR

The key element of the air conditioner is the REFRIGERENT that flows constantly through its mechanisms.

The REFRIGERENT becomes liquid and gives off heat when it is compressed.

It becomes a gas and absorbs heat when the pressure is removed.

The fan blows the air over the cooling coils containing the refrigerant fluid.

The warm air reacts with the refrigerant and in the process refrigerant vaporizes.

The cooled air is blown back into the room. The vaporized refrigerant moves to the compressor,

which pumps it under pressure to the condenser coils. The refrigerant is returned to the cooling coil as a

liquid.

OPERATION OF AIR-CONDITIONER.CONTD

LINGUISTIC VARIABLES INPUT VARIABLES

1. USER TEMPERATURE LOW, MEDIUM, HIGH.

2. TEMPERATURE DIFFERENCE NEGETIVE, ZERO, POSITIVE, LARGE.

3. OCCUPANCY LOW, MEDIUM, HIGH.

OUTPUT VARIABLES

1. FAN SPEED LOW, MEDIUM, FAST.

2. COMPRESSOR SPEED OFF, LOW, MEDIUM, FAST.

3. FIN DIRECTION TOWARDS,MIDDLE, AWAY.

INPUT VARIABLE – USER TEMPERATURE

INPUT MEMBERSHIP FUNCTIONS

USER TEMPERATURE

LOW,

µ(LOW) : 1 0’C≤X≤22’C≤ -X+25/3 22’C≤X≤25’C

0 25’C≤X≤30’C

MEDIUM,

µ(MED): 0 0’C ≤X ≤22’C

X-22/3 22’C ≤X ≤25’C

-X+28/3 25’C ≤X ≤28’C

028’C ≤X ≤30’C

µ(HIGH): 00’C≤X ≤25’C

X-25/325’C≤X≤28’C

128’C≤X≤30’C

[0 25)

(22 28)

(25 30]

HIGH,

INPUT VARIABLE – TEMPERATURE DIFFERENCE


TEMPERATURE DIFFERENCE

µ(ZERO)(X):X+1 -1C ≤X ≤0’C -X+1 0’C ≤X ≤1’C

0 1’C ≤X ≤3’C

µ(POS)(X) : 0 -1’C ≤X ≤O’C

X0’C ≤X ≤1’C -X+21’C ≤X ≤2’C

02’C ≤X ≤3’Cµ(LARGE)(X): 0 1’C ≤X ≤1’C

X-1 1’C ≤X ≤2’C1 2’C

≤ X ≤3’C

µ(NEG)(X): -X -1’C ≤X ≤0’C0

0’C ≤X ≤3’C [-1 0)

(-1 1)

(0 2)

(1, 3]

NEGETIVE

ZERO

POSITIVE

LARGE

INPUT VARIABLE – OCCUPANCY


OCCUPANCY

µ(MED)(X): 0 0 ≤X ≤2 X-2/3 2 ≤X ≤5 -X+8/3 5 ≤X ≤8 0 8 ≤X ≤10

µ(HIGH)(X): 0 0 ≤X ≤5

X-5/3 5 ≤X ≤8

1 8 ≤X ≤10

µ(LOW)(X): 10 ≤X ≤2

-X+5/3 2 ≤X ≤5 0

5 ≤X ≤10

[0 5)

(2 8)

(5 10]

LOW

MEDIUM

HIGH

OUTPUT VARIABLE – FAN SPEED

OUTPUT MEMBERSHIP FUNCTION

TEMPERATURE DIFFERENCE

µ(ZERO)(X):X+1 -1C ≤X ≤0’C -X+1 0’C ≤X ≤1’C

0 1’C ≤X ≤3’C

µ(POS)(X) : 0 -1’C ≤X ≤O’C

X0’C ≤X ≤1’C -X+21’C ≤X ≤2’C

02’C ≤X ≤3’Cµ(LARGE)(X): 0 1’C ≤X ≤1’C

X-1 1’C ≤X ≤2’C1 2’C

≤ X ≤3’C

µ(NEG)(X): -X -1’C ≤X ≤0’C0

0’C ≤X ≤3’C [-1 0)

(-1 1)

(0 2)

(1, 3]

NEGETIVE

ZERO

POSITIVE

LARGE

OUTPUT VARIABLE –COMPRESSOR SPEED


COMPRESSOR SPEED

µ(LOW)(X): 0 0 ≤X ≤30 X-30/15 30

≤X ≤45 -X+65/20 45

≤X ≤650

65 ≤X ≤100

µ(MED)(X): 0 0 ≤X ≤45 X-45/20 45 ≤X ≤65 -X+80/15 65 ≤X ≤80

080 ≤X ≤100

µ(FAST)(X): 0 0 ≤ X ≤ 65 X-65/15 65 ≤X ≤

801

80 ≤ X ≤ 100

[30 65)

(45 80)

(65 100]

LOW

MEDIUM

FAST

µ(OFF)(X): 1 0 ≤X ≤30

-X+45/1530 ≤X ≤45

045 ≤X ≤100

OFF

[0, 45)

OUTPUT VARIABLE – FIN DIRECTION


µ(TOWARDS)(X): 1 0 ≤X ≤20 -X+45/25 20 ≤X

≤45 0 45

≤X ≤90

µ(AWAY)(X): 0 0 ≤X ≤45

X-45/25 45 ≤X ≤70

1 70 ≤X ≤90

[0 45)

(45 90]

µ(NO OP)(X): 0 0 ≤X ≤20 X-20/25 20 ≤X ≤45 -X+70/25 45 ≤X ≤55

0 55 ≤X ≤90

TOWARDS

AWAY

NO OPERATION

(20 55)

FIN DIRECTION

MAMDANI MODEL- RULESUSER

TEMPERATUREOCCUPANCY TEMPERATURE

DIFFERENCEFAN SPEED COMPRESSOR

SPEEDFAN DIRECTION

LOW AND LOW AND NEGETIVE THEN MEDIUM AND OFF AND AWAY

LOW AND LOW AND ZERO THEN FAST AND OFF AND NO OPERATION

LOW AND LOW AND POSITIVE THEN MEDIUM AND LOW AND TOWARDS

LOW AND LOW AND HIGH THEN FAST AND LOW AND TOWARDS

LOW AND MEDIUM AND NEGETIVE THEN FAST AND MEDIUM AND TOWARDS

LOW AND MEDIUM AND ZERO THEN MEDIUM AND FAST AND NO OPERATION

LOW AND MEDIUM AND POSITIVE THEN FAST AND MEDIUM AND TOWARDS

LOW AND MEDIUM AND HIGH THEN MEDIUM AND FAST AND TOWARDS

LOW AND HIGH AND NEGETIVE THEN LOW AND FAST AND TOWARDS

LOW AND HIGH AND ZERO THEN MEDIUM AND FAST AND NO OPERATION

LOW AND HIGH AND POSITIVE THEN MEDIUM AND FAST AND TOWARDS

LOW AND HIGH AND HIGH THEN FAST AND FAST AND TOWARDS

USER TEMPERATURE

OCCUPANCY TEMPERATURE DIFFERENCE

FAN SPEED COMPRESSOR SPEED

FAN DIRECTION

MEDIUM AND LOW AND NEGETIVE THEN MEDIUM AND OFF AND AWAY

MEDIUM AND LOW AND ZERO THEN MEDIUM AND OFF AND NO OPERATION

MEDIUM AND LOW AND POSITIVE THEN LOW AND MEDIUM AND TOWARDS

MEDIUM AND LOW AND HIGH THEN MEDIUM AND MEDIUM AND TOWARDS

MEDIUM AND MEDIUM AND NEGETIVE THEN MEDIUM AND MEDIUM AND TOWARDS

MEDIUM AND MEDIUM AND ZERO THEN MEDIUM AND MEDIUM AND NO OPERATION

MEDIUM AND MEDIUM AND POSITIVE THEN MEDIUM AND FAST AND TOWARDS

MEDIUM AND MEDIUM AND HIGH THEN FAST AND FAST AND TOWARDS

MEDIUM AND HIGH AND NEGETIVE THEN MEDIUM AND MEDIUM AND TOWARDS

MEDIUM AND HIGH AND ZERO THEN FAST AND MEDIUM AND NO OPERATION

MEDIUM AND HIGH AND POSITIVE THEN FAST AND FAST AND TOWARDS

MEDIUM AND HIGH AND HIGH THEN MEDIUM AND FAST AND TOWARDS

USER TEMPERATURE

OCCUPANCY TEMPERATURE DIFFERENCE

FAN SPEED COMPRESSOR SPEED

FAN DIRECTION

HIGH AND LOW AND NEGETIVE THEN FAST AND OFF AND AWAY

HIGH AND LOW AND ZERO THEN LOW AND LOW AND NO OPERATION

HIGH AND LOW AND POSITIVE THEN MEDIUM AND MEDIUM AND TOWARDS

HIGH AND LOW AND HIGH THEN FAST AND MEDIUM AND TOWARDS

HIGH AND MEDIUM AND NEGETIVE THEN FAST AND LOW AND TOWARDS

HIGH AND MEDIUM AND ZERO THEN FAST AND MEDIUM AND NO OPERATION

HIGH AND MEDIUM AND POSITIVE THEN FAST AND FAST AND TOWARDS

HIGH AND MEDIUM AND HIGH THEN FAST AND FAST AND TOWARDS

HIGH AND HIGH AND NEGETIVE THEN FAST AND MEDIUM AND TOWARDS

HIGH AND HIGH AND ZERO THEN FAST AND MEDIUM AND NO OPERATION

HIGH AND HIGH AND POSITIVE THEN FAST AND FAST AND TOWARDS

HIGH AND HIGH AND HIGH THEN FAST AND FAST AND TOWARDS

FUZZY MATCHING DEGREE

FUZZY MATCHING DEGREEUSER TEMPERATURE low by

USER TEMPERATURE MEDIUM by (67%)

TEPMPERATURE DIFFERENCE POSITIVE by (75%)

TEMPERATURE DIFFERENCE is LARGE by (25%)

USER TEMPERATURE TEMPERATURE DIFFERENCE OCCUPANCY

Max(UT)=max[0.33, 0.67]=0.67 Max(TD)=max[0.75, 0.25]=0.75 Max(occ)=max[1. 1]=1

USER TEMP=24’C TEMP DIFF=1.25’C OCCUPANCY=6

OCCUPANCY MEDIUM BY 1(100%)

INFERENCEMinimum of the 3 membership functions is considered, because of the operation AND

If the USER TEMERATURE is MEDIUM and TEMPERATURE DIFFERENCE is

POSITIVE and OCCUPANCY is MEDIUM then the output FAN SPEED

is MEDIUM

If the USER TEMPERATURE is MEDIUM and TEMPERATURE DIFFERENCE is POSITIVE and

OCCUPANCY is MEDIUM then the output COMPRESSOR SPEED is FAST

If the USER TEMPERATURE is MEDIUM and TEMPERATURE DIFFERENCE is POSITIVE and OCCUPANCY is MEDIUM then the output FAN DIRECTION is TOWARDS.

DEFUZZIFICATION The membership function

considered is 0.67 and clipping is done according to the rules.

The POSSIBILTY DISTRIBUTION is [43.4, 56.6] for FAN SPEED

Therefore mean ie FAN SPEED = 50 units

The POSSIBILTY DISTRIBUTION is [75.05, 100] for COMPRESSOR SPEED

Therefore mean ie COMPRESSOR SPEED=87.5 UNITS.

The POSSIBILITY DISTRIBUTION is [0, 28.25] for FIN DIRECTION.

Therefore mean ie FIN DIRECTION is TOWARDS = 14

FUZZY SURFACE

I/P USER TEMPERATURETEMP DIFFERENCE

0/P COMPRESSOR SPEED

I/P USER TEMPERATURETEMP DIFFERENCE

0/P FIN DIRECTION

I/P USER TEMPERATUREOCCUPANCY

O/P FAN SPEED


O/P COMPRESSOR SPEED


O/P FIN DIRECTION

I/P TEMP DIFFERENCEOCCUPANCY

O/P FAN SPEED


O/P COMP SPEED


O/P FIN DIRECTION

I/P USER TEMPERATURE

TEMP DIFFERENCEO/P FAN SPEED

OUTPUT VARIABLE – FAN SPEEDTAKAGI-SUGINO METHOD

LOWX=20.41

MEDIUMX=50FAST

X=77.08

OUTPUT VARIABLE – COMPRESSOR SPEED

TAKAGI-SUGINO METHOD

OFFX=31

LOWX=45

MEDIUMX=65

FASTX=85.9

OUTPUT VARIABLE – FIN DIRECTIONTAKAGI-SUGINO METHOD

TOWARDSX=17.05

MIDDLEX=45

AWAYX=72.95

FUZZY MATCHINGTAKAGI-SUGINO METHOD

FUZZY MATCHINGUSER TEMPERATURE low by

USER TEMPERATURE MEDIUM by (67%)

TEPMPERATURE DIFFERENCE POSITIVE by (75%)

TEMPERATURE DIFFERENCE is LARGE by (25%)

USER TEMPERATURE TEMPERATURE DIFFERENCE OCCUPANCY

Max(UT)=max[0.33, 0.67]=0.67 Max(TD)=max[0.75, 0.25]=0.75 Max(occ)=max[1, 1]=1

USER TEMP=24’C TEMP DIFF=1.25’C OCCUPANCY=6

OCCUPANCY MEDIUM BY 1(100%)


DEFUZZIFICATIONFAN SPEED = 61.3

If the USER TEMPERATURE is MEDIUM and TEMP

DIFFERENCE is POSITIVE and OCCUPANCY is

MEDIUM then FAN SPEED is MEDIUM

COMPRESSOR SPEED = 91.3

If the USER TEMPERATURE is MEDIUM and TEMPERATURE DIFFERENCE is POSITIVE and OCCUPANCY is MEDIUM then

the output COMPRESSOR SPEED is FAST

If the USER TEMPERATURE is MEDIUM and TEMPERATURE DIFFERENCE is POSITIVE and

OCCUPANCY is MEDIUM then the output FAN DIRECTION is

TOWARDS.

FIN DIRECTION = 17.1


REFERENCEShttp://www.ijser.org/researchpaper%5CIntelligent-Air-Conditioning-System-using-Fuzzy-Logic.pdf

http://www.sciencedirect.com/science/article/pii/S1364032104001200

http://aptnk.in/profile/papers/Fuzzy-Logic-Control-of-Air-Conditioners.pdf

http://www.ijser.org/researchpaper/Intelligent-Air-Conditioning-System-using-Fuzzy-Logic.pdf



