Electrical Machines What is the frequency of a alternator, if P = number of poles and N = revolution made per second? 120 / PN Hz. 120P / N Hz. PN / 2 Hz. 120N / P Hz. 120 / PN Hz. 120P / N Hz. PN / 2 Hz. 120N / P Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A bipolar dc machine with interpoles has a main-pole flux of ф per pole and an interpole flux of Фᵢ per pole. The yoke of the machine is devide into four quadrants by the main-pole axis and The commutation axis. The flux-distribution in the quadrants will be ½ ( ф + фᵢ ) in all the four quadrants ½ ( ф + фᵢ ) in two adjacent quadrants and ½ ( ф - фᵢ ) in the remaining two quadrants ½ ( ф + фᵢ ) in two diametrically opposite quadrants and ½ ( ф - фᵢ ) in the remaining two Quadrants ½ ( ф - фᵢ ) in all the four quadrants ½ ( ф + фᵢ ) in all the four quadrants ½ ( ф + фᵢ ) in two adjacent quadrants and ½ ( ф - фᵢ ) in the remaining two quadrants ½ ( ф + фᵢ ) in two diametrically opposite quadrants and ½ ( ф - фᵢ ) in the remaining two Quadrants ½ ( ф - фᵢ ) in all the four quadrants ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3-phase induction motor, torque and supply voltage are related as T ∝ 1/V² T∝ V² T ∝ V T ∝ 1/V T ∝ 1/V² T∝ V² T ∝ V T ∝ 1/V 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? 45 HZ 48.5 Hz 50 Hz 48 Hz 45 HZ 48.5 Hz 50 Hz 48 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The breakdown torque of a synchronous motor varies as applied voltage V 1/V² V² 1/V applied voltage V 1/V² V² 1/V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In speed control of DC Series motor, speed lower than the rated speed can be obtained by Any of the above. Connecting an additional resistance in the armature circuit. Connecting an additional resistance in the field circuit. Connecting an additional resistance in stator circuit. Any of the above. Connecting an additional resistance in the armature circuit. Connecting an additional resistance in the field circuit. Connecting an additional resistance in stator circuit. ANSWER DOWNLOAD EXAMIANS APP