how speed control of induction motor?
Answers were Sorted based on User's Feedback
Answer / eugene
Speed control control of induction type motors (also known
as squirral cage motors), are mainly achieved by
controlling the input voltage to the motor terminals. This
can be done by altering the frequency of the supply by
using a Variable Speed Controller, or if the speed control
is allowed to be multi-staged, resistive circuits can be
inserted using contactors and resistors, thus limiting the
voltage applied.
Is This Answer Correct ? | 10 Yes | 3 No |
1.control from stator side
a.by changing applied voltage
b.by changing stator no. of poles
c.by changing applied frequency
2.control from rotor side
a.by rotor rheostate
b.by cascade operation
c.by injecting emf in rotor ckt.
Is This Answer Correct ? | 7 Yes | 0 No |
Answer / karpagam
The motor speed control for controlling the speed
of an electric induction motor is by modulating the
amplitude and frequency of the driving voltage. When load
increases the speed control controls the speed of the
machine so as to be relatively constant with respect to
frequency of the driving voltage. Obviously,the speed
control controls the amplitude of driving voltage in
proportion to the square of the frequency.
Is This Answer Correct ? | 4 Yes | 1 No |
Why Phase to Neutral get spark
What mean by MLTP
75kw drive operated motor current fluctuation from(85-130)ampere.current setting in drive is 130amp.sometimes motor trip when current limit cross 130amps.I change the drive. still current fluctuate between 80-130amps but in this time motor not trip,current setting in drive is 130amps.where is the problem?
What is the recommended voltage gap between Live and Earth and ,Earth and Neutral.If these are exceded what is the solution.
how i calculate the size in mm of the LT 4 core cable for 100 HP inductive motor pump
When we use air circuit breaker, it has O/L protection ,time delay SC protection, Instataneous SC protection & ground fault protection. They all have some setting range. But what is the suitable/allowable setting for the above protection which will be safe for the equipment? For example-O/L protection setting have a range of (0.4,0.45,0.5,0.55,0.6,0.65,0.7,0.8,0.9,1.0)xIn Time delay SC protection have a range of (1.25,1.5,2,3,4,6,8,10,12)xIn Time delay setting is 0.02,0.1,0.2,0.3,0.4 Instataneous setting is fixed to 20xIn Gound fault setting is given 100A,300A,600A,900A,1200A This setting are for 2500A ACB. So what will be the basic allowable setting for the above protection? is there any formulae to calculate this<
How to calculate the Harmonics losses in terms of cost/unit.
How single phase & 3 phase motor select rotating direction ie clockwise/anticlockwise
Which oil can be used in transformer?
What is meant by Floating Neutral? how to prent
why we use REF and Differential Protection in one transformers?my doubt is both protections are operated in internal fault only.why we want to use 2 protections?please clarify.
.php|