Answer Posted / sumit
VFD acts as a conveter between the motor and main
supply.suppose a motor is carrying a load(coupled to a
pump to lift water )then after sometime load decreases
means requirement of water reduces means pump now needs to
pick less water but torque of motor will have to be same
because pump inertia(m*r*r) and acceleration is constant
stant but now we need to maintain less pressure(to pick
less water) and pressure comes from speed of pump (directly
proportional to motor speed) thus we need to decrease speed
of motor but at the same time as mentioned above constant
torque is must.so decrease voltage to maintain a constant
ratio of voltage/frequency.voltage decreases so currenet
from vfd decreases so line current drawn by vfd from mains
decreases and thus power drawn decreases.and reduction of
speed is done by vfd.
| Is This Answer Correct ? | 3 Yes | 1 No |
Post New Answer View All Answers
How can we calculate the transformer rating if the load calculated is 1000KW (11Kv Supply)?
WHAT ARE THE DISADTAGES OF SINGLE-WIRE-EARTH-RETURN SYSTEM USED FOR RURAL ELECTRIFICATION?
We have 750KVA DG set, we want to introduce REF relay with 1250/1A,CL PS,Current transformers.The lead distance of 2.5mm copper flexible cable from CT to relay is around 5mtrs.We would like to know the knee point votage(VK) & IM calculion for CT's
full form of flry b
why ht motors are star connected?
how to interlock 3 incomer-ACB,1 buscoupler ACB,... pls answer this question and if possible send me the ckt diagram..haifriends2910@gmail.com
What Should be the value of Vector Surge angle at Tripping and how to calculate it?
details of oil cell size of Breakdown voltage test of tranformer oil details as per Standardswith mushroom electrodes?
As we use capacitior bank in 3ph ckt for improvement of PF, why not we use capacitor in single phase domestric use, at our house their are many inductive equipments,like fan,mixer,tube choke,air conditioner they also draw PF... by using capacitor can they improve PF. if yes--what are advantage and how to connect a capactor in single ph,and which type of capacitor if no- what are disadvantages.
Why does the Solid state Rectifiers for 3-ph brake motors sometimes have 2 & sometimes 3 output terminals?
How to select a contactor? How many types of contactors are available
What is a surge supressor why its is used in synchronous generators
what is the carona effects meaning in HT line transmmission system
what is ratio of copper wire size and current ?
Is neutral transformer can be called as control transformer?