Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3, 4, 5 1, 2, 3 2, 3, 4 2, 3 ,5 2, 3, 4, 5 1, 2, 3 2, 3, 4 2, 3 ,5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following methods of speed control is not affected through stator side? Change of supply frequency. Change of number of pole. Change of supply voltage. Change of rotor resistance. Change of supply frequency. Change of number of pole. Change of supply voltage. Change of rotor resistance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC Shunt Motor if the load current increases then field flux decreases remains constant. decreases. increases. decreases remains constant. decreases. increases. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The damper windings also called the squirrel cage windings or damper grids consists of short-circuited copper bars embedded in the field pole faces. both (A) and (B). are provided in a synchronous motor to make it self starting. are provided on the stator for improving power factor. consists of short-circuited copper bars embedded in the field pole faces. both (A) and (B). are provided in a synchronous motor to make it self starting. are provided on the stator for improving power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To increase starting torque of a 3-phase slip ring induction motor, preferred method is to increase None of these supply voltage rotor resistance supply frequency None of these supply voltage rotor resistance supply frequency ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The principle of dynamically induced emf is utilized in transformer. thermocouple. choke. generator. transformer. thermocouple. choke. generator. ANSWER DOWNLOAD EXAMIANS APP