whose motors self starting synchronous or Induction motor?give
fact reason why not self starting another mother
Answer Posted / yogesh
Single phase induction motor or synchronous are motor not self starting motors. In case of 3 phase, induction motor is self starting one. Synchronous motor is not a self starting one. Reason: if 3 phase supply is applied to stator, the rotating magnetic field(RMF) is produced with sync speed which will induce the emf on the rotor and produce flux. The rotor flux interacts with stator flux and rotor will rotate to catch the speed of stator(rotating magnetic field speed i.e. Sync speed). In sync motor the rotor is either in salient or non salient pole. If 3 phase supply is given to stator, RMF is prodused. Apply DC supply to the rotor(LET Salient pole rotor with 2 poles). Now N , S poles are induced in rotor. If at one instance stator N pole is nearer to rotor S pole, at that time the rotor tries to move in clock wise direction (for eg.). Suddenly the stator poles(rmf) will move to the another portion of the stator. Let stator S Pole is nearer to rotor S pole, at that time rotor will try to move in anti clk wise direction because stator N pole is at exactly in opposite direction to that of rotor axis. Since RMF is rotating in sync speed the rotor can not move in both clk wise and anti clk wise direction. The result is both clk and anti clk torques get cancelled each other. The rotor does not rotate. To make the sync motor self starting we can provide damper windings on the pole faces of rotor that could act as induction motor at starting then after running of the rotor switch on the DC supply to rotor. Now magnetic locking takes place between stator poles and rotor poles. Now the motor runs in sync speed.
| Is This Answer Correct ? | 0 Yes | 0 No |
Post New Answer View All Answers
what is the carona effects meaning in HT line transmmission system
upto how much low RPM we will run the commercial motor which is run through VFD without any problem occurs in motor.Motor rating Duty is S1 & RPM is 1400.
whatis the commertial spec. of distribution boards ?
what is the difference between c power and U power acb breaker
As per standard, transformer body earthing and other Equipment earthing (Equipment earthing) did not connect. but in LT side termination we are doing metal glanding in both side Transformer to PCC Panel through armoured cable, now X'mer body earthing and PCC Pane earthing (Equipment earthing) both are connect.is this safe for X'mer or other equipment?
define hysteresis loss, eddy current loss and windage loss
how u select control transformer for a mccb panels or any panels?for expample we hav 440 volts maim supply and control volts is 230v?
How to calculate KVA/VA rating of PT or CT from primary & secondary voltage or primary & secondary current?
What is sink and source?
What is real time power factor control panel(RTPFC)?
how to calculate the no load current in transformer?
How it can worked plc based electrical system And which type of software using.
What are the factors which influence the choice of specific magnetic and electric loadings of a synchronous machine?
What are conduct on the testing in cf in ur site?
what is the prinsiple of dc motor and construction and working ,application of dc motor.