2. The Project is divided in to four section
ELEKTRA – FAURNDAU MOTOR –its working and speed control
principles
Drawback of ELEKTRA – FAURNDAU MOTOR
Mitigation of Problem Caused by ELEKTRA – FAURNDAU
MOTOR
a. By appropriate selection of Motor
b. By using Upgrading Technology
Setting a VFD for different Application
4. The Motor is a three phase motor
This motor is variable in speed
It is simple and Efficient
5. Air intake
cowl
Cover for
air intake
cowl
Slipring
unit
Louvred
Cover
Brush
Yoke
Primary
terminal
board
Terminal
box cover
Control Unit
6. The primary winding in the rotor is directly connected to the three
phase and generates an electromagnetic field
It induces a voltage in regulating winding and stator winding
A partial voltage which can be varied by altering the brush position,
is tapped off from the commutator and fed to stator winding.
A sum voltage is formed that determines the current and the torque
developed by the motor.
Speed will vary slightly with load and it can be adjusted by
displacing the brushes.
7. The main power supply is connected to the terminal U,V,W
on the primary terminal board.
For speed regulation the control circuit must be connected
through the interlock switch.
The pilot motor is connected at its terminal board and must be
coupled to the control unit
Push button “speed up” is depressed, the motor speed move
towards the maximum speed and return to minimum speed when
press the speed down push button.
8. Control shaft
Coupling
Bearing bush
Limit switch for minimum speed
Limit switch for maximum speed
Speed selector
Speed indicator
Speed switch
11. Sparking on the commutator
Causes:
a. commutator very dirty,
b. brushes jammed,
c. brushes pressure too low,
d. brushes worn
Result:
a. Motor trip off,
b. loss of production
Remedy:
a. Change and inspect the brushes on regular basis
12. Motor over heat:
CAUSES:
a. The friction between commutator and brushes.
Result:
The built in thermostat give the interrupted signal to control circuit and
motor is trip off.
REMEDY:
a. Clean the motor thoroughly
b. Proper ventilation of motors should be ensured.
c. Examine the health of brushes on regular interval.
13. QTY TYPE POWER COST(SR)
1 AC MOTOR 45KW 161928
1 AC MOTOR 30 KW 143936
CAPITAL COST
19. Speed control of DC motor can be achieve by
a. Changing armature voltage
increasing the armature voltage will increase the speed
b. reducing the field current will increase the speed
20. a. Few low/medium speed applications
b. Commutator Sparking,
c. Rubbing of Carbon Brushes,
d. over heating of motor on regular interval
e. Expensive compared to AC motors.
21. Synchronous motor
Induction motor
Synchronous motor:
Since the synchronous motor runs at a constant speed so it is
not appropriate alternator of Elecktra-Farandau Motor.
22. INDUCTION MOTOR will suitable in this situation
for following reason:
It is a variable speed motor and its speed depends on
applied frequency Ns=120f/p
Since it has no commutator and brushes mechanism
involved so these faults are eliminated.
They are inexpensive (half or less of the cost of a DC
motor)
Easy to maintain
24. Rotor
• Squirrel cage: conducting bars in parallel slots
Stator
• Stampings with slots to carry 3-phase windings
• Wound for definite number of poles
25. a. Electricity is supplied to the stator, which generates a magnetic
field.
b. This magnetic field moves at synchronous speed around the rotor,
which in turn induces a current in the rotor.
c. The rotor current produces a second magnetic field, which tries to
oppose the stator magnetic field, and this causes the rotor to
rotate.
Electromagnetics
Stator
Rotor
26. MEZ CZECH REPUBLIC
3 PHASE MOTOR
14BG 223-4AA90-Z
V HZ A KW CO
S
1/mi
n
wt
380 50 87 45 0.8
6
1475
660 50 300
kg
380 60 84
45 0.8
6
1770
660 48
27. QTY TYPE POWER COST (SR)
1 AC INDUCTION
MOTOR
45 KW 7000
1 AC INDUCTION
MOTOR
30 KW 4000
1 DELTA INVERTER 45 KW 10,000
1 DELTA INVERTER 30 KW 6000
28. Cost of Electra-Faurandau motor=161928 SR
Cost of AC Induction motor +DELTA INVERTER
= 7000 SR
Cost Saving = 144928
%Saving =89 %
29. The problems which occurs when we start large
motors (above 7.5hp) connected to the power
system are
High inrush current during starting, typically six full
load current.
Motors with high inertia loads requires up to three
times rated power during starting.
Large frequency and voltage drop in the power
system.
Tripping of other motors connected to the system
bus.
30. The above problems can be solved by:
By reduced voltage starting methods:
This method is adopted universally for the starting of large motors.
31. Direct Online Starting
STAR-DELTA Starting
Auto transformer starting.
Variable frequency derives
32. Stator of motor is directly connected to three phase
supply.
Motor takes starting current of 5-7 Times of FLC
current.
Such large current causes objectionable voltage drop
/dip in supply line consequently the operation of other
equipment is affected(Trip off).
33. Delta starting is when the motor is connected in STAR during the
starting sequence. When the motor has accelerated to close to the
normal running speed, the motor is connected in DELTA.
Due to this following positive results are attained.
The voltage across each winding is reduced by a factor of the
square root of 3.
Starting current is reduced to one third of the DOL start current
Starting torque reduction to one third of the DOL starts torque.
Less stress on motor shaft and strip gears at starting.
34. Disadvantages:
Large current and torque transient produced at the time of switching.
Causes severe stress on the equipment at time of switching.
Shafts twisted, and rotors loosened on shaft
35. This method uses transformer action to reduce the voltage applied
to the motor and current seen by the supply. An improved
torque/amp ratio is achieved and starting current is typically
3*FLC depending on the voltage tapping selected.
Disadvantages:
Large size
Cost is high
High transient current and torque at the time of switching.
shaft may break at transient switching.
36. A variable-frequency drive (VFD) is a system for controlling the
rotational speed of an (AC) electric motor by controlling the
frequency of the electrical power supplied to the motor
Variable-frequency drives are also known as adjustable-frequency
drives (AFD), variable-speed drives (VSD), AC drives or inverter
drives.
37. Speed variation.
Heavy load inertia starting.
High starting torque requirements.
Low starting current requirements.
High efficiency at low speed.
High power factor.
38. Variable frequency drives operate under the principle that the
synchronous speed of an AC motor is determined by the
frequency of the AC supply and the number of poles in the stator
winding.
Mathematically:
a. RPM=120*F/P
b. voltage =Nc* phi(flux)*w ; where Nc=Number of coils.
c. voltage=Nc*phi*2*pie*f where w=2*pie*f
d. Hence:RPM directly proportional to voltage
The speed of an induction motor is slightly less than the
synchronous speed.
39. A variable frequency drive system generally consists:
a. AC motor
b. Variable frequency controller
c. Operator interface
40. a. VFD MOTOR(AC motor):
The motor used in a VFD system is usually a three-phase induction motor.
b.VFD CONTROLLER:
i)Internal circuit diagram:
41. ii)Working of VFD Controller:
The usual design first converts AC input power to DC intermediate
power using a rectifier bridge.
The DC intermediate power is then converted to quasi-sinusoidal AC
power using an inverter switching circuit
insulated gate bipolar transistors (IGBTs) are used in most VFD inverter
circuits.
Achieve variable motor voltage via pulse-width modulation
With PWM voltage control, the inverter switches are used to construct a
quasi-sinusoidal output waveform
42. c.VFD Operator Interface:
The operator interface provides a means for an operator to start
and stop the motor and adjust the operating speed.
The operator interface often includes an alphanumeric display
and/or indication lights and meters to provide information about
the operation of the drive.
43. When a VFD starts a motor, it initially applies a low
frequency and voltage to the motor.
The starting frequency is typically 2 Hz or less.
Starting at such a low frequency avoids the high inrush
current that occurs when a motor is started by simply
applying the mains voltage by turning on a switch.
When a VFD starts, the applied frequency and voltage are
increased at a controlled rate or ramped up to accelerate
the load without drawing excessive current.
This starting method typically allows a motor to develop
150% of its rated torque while drawing only 150% of its
rated current
A VFD can be adjusted to produce a steady 150% starting torque
from standstill right up to full speed while drawing only 150%
current
45. Parameters
The VFD-B parameters are divided into 12 groups
Group 0: User Parameters
Group 1: Basic Parameters
Group 2: Operation Method parameter
Group 3: Output Function Parameters
Group 4: Input Function Parameters
Group 5: Multi-Step Speed and PLC Parameters
Group 6: Protection Parameters
Group 7: Motor Parameters
Group 8: Special Parameters
Group 9: Communication Parameters
Group 10: PID Control Parameters
Group 11: Fan & Pump Control Parameters
46. APPLICATION PURPOSE PARAMETER
PUMP AND EXTRUDER
MOTOR
To protect
machines and to
have continuous/
reliable operation
06-00~06-05,03-00~03-03
08-14~08-21, 01-00~01-04
General application For safety 03-00~03-03
General application To run, stop,
forward and
reverse by external
terminals
02-05
04-04~04-09
Auto turntable for
conveying machinery
Switching
acceleration and
deceleration times
by external signal
01-09~01-12
01-18~01-21
04-04~04-09
48. Analog voltage Input (AVI)
Analog current Input (ACI)
Auxiliary analog voltage input (AUI)
Analog output meter (AFM)
Analog control signal (ACM)
49. FWD Forward-Stop command
REV Reverse-Stop command
JOG Jog command
EF External fault
TRG External counter input
MI1~MI6 Multi-function Input
DCM Digital Signal Common
51. Up and Down
Key
Set the parameter
number
Left Key
Moves Cursor to
the left
JOG
Jog frequency
operation
User Defined
Units
Status Indicator
Output Frequency
Status Indicator
Frequency
Command
Status Indicator
LED Display
indicates frequency,
current, voltage and save,
etc.
Model Number
Status Display
Display of drive
status
Mode
Display mode
selectorPROG/DATA
Used to enter
programming
Parameters
Stop/Reset
Run Key
52. DISPLAY Message Description
Displays the AC drive Master
Frequency
Displays the actual output
frequency present at terminals
U/T1, V/T2, and w/T3
User defined unit
Displays the output current present
at terminals U/T1, V/T2, and
W/T3.
Displays the AC motor drive
forward run status
Displays the AC motor drive
reverse run status
Displays the selected parameter.
External Fault
54. In the ac power network ,the total power
supplied to the load ismore than the actual
power consumed by the load.
Ractive power has no use and put extra burden
to the load.resulting over heating of
conductor,power loss and poor voltage
regulation.
Voltage imbalance causes rise in temperature
of motor.
55. Voltage will be improved
Heat loss minimized
Xfmr loss will be reduced
Distribution loss will be reduced.
Reduce the 3rd harmonic effect…
56. Good character is more to be praised than outstanding talent. Most
talents are, to some extent, a gift. Good character, by contrast, is not
given to us. We have to build it piece by piece-by thought, choice,
courage and determination
SYED ATIF NASEEM