what is cogging and crawling
Answer Posted / sukhjeet saini
When rotor bars are made to run parallel with stator , the
torque rises & falls correspondingly causing more
pulsations. This is termed as cogging in other qords
magnatic locking. This is reduced by making the rotor bars
run at an angle to the stator ie crawling in order to make
the torque uniform.
Crawling on the other hand signifies running of motor at
almost one seventh of the rated spped due to interference
of seventh harmonics.
|Is This Answer Correct ?||144 Yes||43 No|
How many double suspension hardware fittings are required on a double circuit transmission tower?
Why reactive power is needed in a power system? How is it being absorbed or delivered by alternators? For reactive power control we are changing excitation but reactive power absorbing or delivering related to stator. How these two are interlinked? i want a detailed explanation with necessary expressions and figures?
What types of CMOS memories have you designed? What were their size? Speed? Configuration Process technology?
IN electrical field, WHAT ALL THINGS THE CUSTOMER WILL ASK WHILE ORDERING FOR LT PANEL (ALL TYPES OF LOW TENSION PANEL)
In synchronous motor, how the field current is related to armature current..i know its inversely proportional..but concept wise...i was nt clear....pls help me...
in dc shunt motor if field winding is shorted then
What is the function of Governor in Hydro Power Station? What is the Function of Lightning Arrestor Voltage Transformer (LAVT)?
what is the defination of Cable database? What are the points are considered while preparing cable database? Is there any sample available for cable database?
What is the need of earthing transformer for delta side of a transformer. (Think of a line section between a star/delta transformer at a grid substation and delta/star transformer at a village. An earthing transformer is there at the delta side of the star/delta transformer at grid substation). As there are no ground reference there will not be fault current if a one phase is grounded. Further L-L phase will be sensed by the primary side of star/delta transformer as a L-G fault. So why an earthing transformer is required at delta side
what is the safty of poly phase tranformer?
what is frequency response?
what is meant by CT`s saturation ? Can we use Metering CT`s with Protetection CT`s ?
What the main causes of transient interruptions on Over-Head Distribution Lines?
EXPLAIN THE ESSENTIAL FACTORS WHICH INFLUENCES THE CHOICE OF SITE FOR A HYDRO ELECTRIC POWER PLANT
WHAT IS MEANT BY TV TERMINAL IN 500MVA TRANSFORMER?