Electrical Machines What is the highest possible speed of turbo alternators? 1500 rpm 1000 rpm 3000 rpm 4000 rpm 1500 rpm 1000 rpm 3000 rpm 4000 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two synchronous generators operating in parallel 200 MW and 400 MW respectively. The drooping characteristics of their governors are identical as 4% from no load to full load. Consider the governors operating at 50Hz on no load. What is the operating frequency, if the load is 600 MW? 48 Hz 45 HZ 50 Hz 48.5 Hz 48 Hz 45 HZ 50 Hz 48.5 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The demagnetising component of armature reaction in a DC generator increases armature speed. results in sparking trouble. reduces inter poles flux density. reduces generator emf. increases armature speed. results in sparking trouble. reduces inter poles flux density. reduces generator emf. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of a DC series motor is Proportional to the armature current. Proportional to the square of the armature current. Proportional to field current. Inversely proportional to the armature current. Proportional to the armature current. Proportional to the square of the armature current. Proportional to field current. Inversely proportional to the armature current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Semi closed slots or totally closed slots are used in induction motors, essentially to improve starting torque increase pull out torque decrease starting torque reduce magnetising current and improve power factor improve starting torque increase pull out torque decrease starting torque reduce magnetising current and improve power factor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchronous generator is feeding a zero power factor (lagging) load at rated current. The armature reaction is magnetizing. cross – magnetizing. ineffective. demagnetizing. magnetizing. cross – magnetizing. ineffective. demagnetizing. ANSWER DOWNLOAD EXAMIANS APP
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