NEW GENERATION MOTORS

1. WELCOME TO THE PRESENTATION ON
•ENERGY EFFICIENT MOTORS
•VARIABLE FREQUENCY DRIVE MOTORS

2. ENERGY EFFICIENT MOTORS
• WHAT IS ENERGY EFFICIENT MOTOR?
•WHAT IS THE NEED OF ENERGY EFFICIENT MOTOR?

3. ENERGY EFFICIENT MOTOR
An energy efficient motor produces
the same output
but uses less electrical power ( KW )
than a standard motor.

4. ENERGY EFFICIENT MOTOR
• Till 1980s, Electrical motor design was done based on the minimum motor
first cost.
• Materials used in stator and rotor cores, copper wires in windings etc, were
minimum quality and quantity just to deliver the required output.
• But from 1990s, the demand and cost of energy started increasing steeply.
• Energy saved is energy produced.
• So manufacturers focused to increase the motor efficiency.
70% of global industrial electricity is consumed by electric motors

5. ENERGY EFFICIENT MOTOR
Efficiency = Output
Output + Losses
LOSSES :
IRON LOSSES
FRICTION & WINDAGE LOSSES ---------- FIXED LOSSES
STATOR COPPER LOSSES
ROTOR COPPER LOSSES ------------- VARIABLE LOSSES
(VARY WITH LOAD)
ADDITIONAL LOSSES (STRAY LOSSES)

7. ENERGY EFFICIENT MOTOR
• CORE LOSS IS 2-3% OF RATED OUTPUT
• STRAY LOSSES 1-2 % OF OUTPUT
( HOWEVER 0.5% - 4% IS NOT UNCOMMON)
•FRICTION AND WINDAGE LOSS 1-2%
( PERCENTAGE DECREASES AS MOTOR SIZE INCREASES )

8. ENERGY EFFICIENT MOTOR
FIXED/NO LOAD LOSSES
•Core Losses
•Friction and Windage losses
FACTORS AFFECTING ABOVE
•Type & quantity of Magnetic material used
•Selection and design of Bearings and Cooling Fans

9. ENERGY EFFICIENT MOTOR
LOAD LOSSES
•Stator I2 R losses
•Rotor I2 R Losses
•Stray load losses
FACTORS AFFECTING ABOVE
• Stator conductor size
• Rotor conductor size and material
• Good slot fill
• Optimum Design and manufacture

10. CONSTRUCTION OF HIGH EFFICIENCY MOTORS

11. ENERGY EFFICIENT MOTOR
•STATOR COPPER LOSS OPTIMUM SLOT FILL, LARGER
CONDUCTORS
•ROTOR CORE LOSS LOW LOSS STEEL,THINER LAMINATIONS
•STATOR CORE LOSS LOW LOSS STEEL,THINER LAMINATIONS
•BEARING ,WINDAGE SMALLER COOLING FAN
& FRICTION LOSSES
•STRAY LOSSES - IMPROVED SLOT GEOMERTY, LONG
LENGTH OF STATOR CORE

12. ENERGY EFFICIENT MOTOR
STANDARDS :
•IS 12615 - 2004 (EEF1 and EEF2) SUPERCEEDED BY
IS 12615-2011 (IE SERIES)
•IEC 60034-30: 2008 ( Rotating electrical machines – Part 30:
Efficiency class of single speed ,3 phase, cage induction motor
IE Code was created.)

13. ENERGY EFFICIENT MOTOR
Efficiency Class Description IS
12615 - 2011
IS 12615 2004
IE 1 Standard Efficiency Comparable to EFF 2
IE 2 High Efficiency Comparable to EFF 1
IE 3 Premium
IE4 Super Premium
NEW IE EFFICIENCY CLASSES ARE AS GIVEN BELOW

14. ENERGY EFFICIENT MOTOR
The standard IS 12615:2011 covers low voltage, AC three phase
squirrel cage, single speed induction motors for :
• Rated voltage <= 1000V
• Rated frequency 50Hz
• Rated output between 0.37kW to 375kW
• Frame sizes -315 / 355 L
• 2P, 4P & 6P
• Rated on the basis of continuous duty (S1)

15. ENERGY EFFICIENT MOTOR
•Capable of operating direct on line
• Rated for ambient temperature of 40 deg centigrade &
altitude not exceeding 1000m
• Degree of protection IP44 or superior
• Method of cooling IC 411
• Fixing dimensions as per IS 1231 & IS 2223
•The efficiency levels in IS 12615:2011 are based on test
methods specified in IS 15999 (Part 2/sec 1):2011 / IEC 60034-
2-1:2007.

16. ENERGY EFFICIENT MOTOR
This standard does not cover
• 8P motors
• Pole changing motors ( multispeed motors)
• Motors made exclusively for converter duty application
• Motors completely integrated into the machine. (for example,
pumps, compressors that cannot be tested separately from
the machine )
• Crane & hoist duty motors

17. ENERGY EFFICIENT MOTOR
Kw Frame
size
Speed FL
Current
IE1
standard
IE2
high
IE3
premiu
m
11 160M 2860 21.5 87.6 89.4 91.2
11 160M 1440 22 87.6 89.8 91.4
11 160L 935 23 86.4 88.7 90.3
45 225M 2955 80 91.7 92.9 94
45 225M 1460 69 91.7 93.1 94.2
45 280S 960 87 91.4 92.7 93.7
125 315M 2980 209 93.4 94.5 95.3
125 315M 1480 234 93.4 94.6 95.5
125 315M 970 245 93.4 94.4 95.2
Typical efficiencies of Energy Efficient Motors as per IS 12615-2011

18. ENERGY EFFICIENT MOTOR
•ASSESSING COST EFFECTIVENESS OF ENERGY EFFICIENT
MOTORS :
Savings are calculated as follows
kW - output of motor in kW
•E1 - efficiency of standard motor
•E2- efficiency of energy efficient motor
•k = [Kw/E1 – Kw/E2 ]
•Saving : k X [working hrs] X [days] X [tariff]

19. ENERGY EFFICIENT MOTOR
SAVINGS CALCULATION EXAMPLE FOR A 3.7 KW MOTOR
•Standard motor of : 85 %
•Energy efficient motor : 88.3 %
•Working hours 16 per day,
•Working days 300 in a year,
•Power rate Rs 4.50 per Kwh
• k = [Kw/E1 – Kw/E2 ] = 0.1626
• Savings = 0.1626 X 16 X 300 X 4.5 = Rs 3514 /- per year

20. HOW TO CHOSE ENERGY EFFICIENT MOTOR
The following information need to be given :
• GD2 (Moment of Inertia) and relevant speed of
driven equipment
• Duty cycle/sequence of operation/no. starts/hours
• Speed-Torque diagram of driven equipment
• Method of braking (Electrical or Mechanical )
• Starting Time and Duty Cycle

21. THINGS TO TAKEN CARE BEFORE CHOSING
ENERGY EFFICIENT MOTOR
•Energy efficient cage-induction motors are typically built with more
active material to achieve higher efficiency
•Hence the starting performance of these motors differ somewhat from
motors with a lower efficiency. The locked rotor current increases
approximately by 10 to 15 percent for increase in each level of
efficiency for the same output power.
•For replacing existing motors, this should be checked by the user with
manufacturer for proper sizing of the protective devices.

22. THINGS TO TAKEN CARE BEFORE REPAIRING ENERGY EFFICIENT MOTOR
REPAIR OR REPLACE ?
PROBLEMS ASSOCIATED WITH REWOUND MOTORS
AFTER REPAIRING
•CORE LOSSES ARE HIGHER BECAUSE OT HIGH TEMPERATURE
AND LAMINATION DAMAGE
•HIGHER COPPER LOSSES DUE TO LOW SLOT FILL
•HIGHER FRICTIONAL LOSSES BEARING AND FANS
•EFFICIENCY LOOSES ACCOUNT FROM 0.3 TO 3.4 %
•AVERAGE REPAIR LOSES 1.1%

23. INVERTER DUTY MOTOR

24. A NORMAL MOTOR IN ITS WORKING LIFE
IS SUBJECTED TO FEW SUPPLY RELATED
PROBLEMS THAT HAVE A BEARING ON ITS
PERFORMANCE AND LIFE

25. WITH INCREASING USE OF VARIABLE
FREQUENCY DRIVES IN BOTH EXPANSION UNITS
AS WELL AS THROUGH UP-GRADATION IN
RUNNING UNITS, WE FACE DIFFERENT
CHALLENGES THAT HAVE A BEARING ON LIFE OF
MOTORS

26. ADVERSE EFFECT OF VFDs ON MOTORS
SOME OF THE LIKELY EFFECTS IN USE OF VFD AS FAR AS MOTOR LIFE IS
CONCERNED ARE :
1.REPETITIVE HIGH VOLTAGE SPIKES (INSULATION PROBLEM)
2.HIGH RATE OF RISE OF VOLTAGE (dv / dt )
3.HIGH LEVEL OF HARMONICS IN OUTPUT AS COMPARED TO NORMAL
SUPPLY (POWER QUALITY ISSUE)
4.SHAFT VOLTAGES

27. S.
NO.
PARAMETER MOTOR FED FROM NORMAL SOURCE
1 VOLTAGE WAVEFORM VERY NEARLY SINUSOIDAL
2 COOLING CONSTANT ( ONLY LOAD DEPENDANT)
3 SURGE VOLTAGES RARELY SUBJECTED
4 VOLTAGE STRESSES NORMAL
5 RATE OF RISE OF VOLTAGE NORMAL
6 HEATING NORMAL DUE TO LOW HARMONIC CONTENT
7 BEARINGS NOT SUBJECT TO SHAFT CURRENTS IN GOOD
DESIGN
8 WINDING / INSULATION WELL ESTABLISHED
9 USE OF ENERGY EFFICIENT
MOTORS
POSSIBLE

28. AGAIN, A COMPARISON BETWEEN NORMAL SOURCE AND
VFD SOURCE AS FAR AS LIFE OF MOTOR IS CONCERNED
S.
N
O
.
PARAMETER MOTOR FED FROM NORMAL
SOURCE
MOTOR FED FROM VFD USING
PWM
1 VOLTAGE WAVEFORM VERY NEARLY SINUSOIDAL NOT SINUSOIDAL DUE TO PRESENCE
OF HARMONICS
2 VOLTAGE VARIATION WITHIN LIMITS WITHIN LIMITS
3 SURGE VOLTAGES /
VOLTAGE STRESSES
RARELY SUBJECTED SUBJECTED TO VOLTAGE STRESSES
AND dv/dt EVERY CYCLE
4 HEATING NORMAL DUE TO LOW
HARMONIC CONTENT
HIGHER DUE TO PRESENCE OF
HARMONICS
5 BEARINGS NOT SUBJECT TO SHAFT
CURRENTS IN GOOD DESIGN
SUBJECT TO SHAFT VOLTAGES DUE
TO CAPACITANCES
6 WINDING /
INSULATION
WELL ESTABLISHED EVEN A MOTOR DESIGNED FOR VFD
IS SUBJECTED TO SEVERE STRESSES
EVERY CYCLE
7 USE OF ENERGY
EFFICIENT MOTORS
POSSIBLE WILL NOT BE OF MUCH USE

29. SOME OF THE FEATURES OF INVERTER DUTY MOTORS
1.INCREASING PHASE INSULATION THICKNESS FOR
HIGHER DIELECTRIC STRENGH
2.USE OF INVERTER DUTY WIRE TO IMPROVE
DIELECTRIC WITHSTAND CAPABILITY
3.MULTIPLE DIPPING AND BAKING
4.VPI TREATMENT
5.INCREASING END WINDING BRACING
6.USE OF INSULATED BEARINGS IN HIGHER SIZE
MOTORS (>280 FRAME)