what will happen when excitation of a synchronous machine
is suddenly reduce to zero when it is running at full
load..??

Answer Posted / b. b. shukla

Practically, in this case, The motor will draw a high current and finally the relay/safety equipment will trip the motor, because -- it will try to run like an induction motor with dampening winding bars acting as rotor conductors. but it will not be sufficient to fulfill the load requirement. therefore the motor will draw high current and its speed will slow down and finally zero. Accordingly the back emf of rotor will reduce, motor current will increase and finally the motor will trip/burn out.

Is This Answer Correct ?    11 Yes 3 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

In the Variable Voltage Variable Frequency Drive, how the Voltage and Frequency varied ? Is it varied in the Inverter part of the Drive ? Please give us supporting document if any.

1519


at which voltage level arcing ground is occurs ??????????

1586


what will happen if there is a voltage leakage or current leakage in an electrical train

1509


Explain how you can give the overload setting to any Motor Protection Relay for a HT motors with formula and example?

1654


how to compute kvar in substation feeder to improve power factor and sending voltage

1649






HOW TO CALCULATE ELECTRICAL, MECHANICAL,& OVERALL EFICIENCY OF GAS ENGINE POWER PLANT

1540


why we use copper earthing for neutral while for body GI.

5054


How to set a Zone 1 distance relay for distribution feeder?

1554


Why neutral cable carry current.

1522


Is neutral transformer can be called as control transformer?

1530


what is the IEC standard for Power Cable installation in onshore (like in direct buried ground or above groung)

2140


CAN CU XLPE/PVC CABLE BE USED INPLACE OF LOW NOISE SCREENED CABLE? KINDLY GIVE REASONS

1415


Where I can get the sample question for post of Junior engineer electrical-II For RRB Bhubaneswar.

1702


if 3400kw slipring motor rotor shorting done and motor started on mv drive ,what will be the rotor shoring current

1241


Explain difference between stand by earth fault and residual earth fault protection?

1538