armature
reaction for motor and generator are same but load is connected to
mechanical side for motor and electrical side for electrical.
Explain the cause and effect of Armature reaction in Generator and Dc motor
5. Explain the condition for a DC motor to develop the maximum power. If a DC machine having an armature resistance of 0.5Ω and the full load current of 20 A. Find the induced emf of machine when it acts as: (i) Motor and (ii) Generator
Explain in detail the armature reaction in DC machines.
1) A 220V dc motor has an armature resistance of 0.5 Ω. The full load armature current is 20 A. The starting torque of the motor is 880 N-m, Find the full load speed of the motor. 2) A 220V dc motor developing 25 hp (18.65 kW) runs at a speed of 1000 r.p.m.. Calculate the torque in N-m if the efficiency of the motor is 90%.
3. A 20kW, 250V, 1000rpm shunt excited dc motor has armature and field resistances of 0.2 ohm and 2002. When the motor takes 80A rated current at rated conditions. Draw the equivalent circuit and calculate induced torque at 1200rpm. Explain the starting current limiting methods for DC motors. (30 pts) 4. Explain the conditions for parallel operation of synchronous generators. A three phase, wye connected, synchronous generator is rated 150 MW, 0.85 lagging power factor, 12.6 kV, 60 Hz, and...
In a parallel DC Generator what happens if an additional armature resistance is added to the Generator 2? What happens to the load current of the first generator and second generator?
An armature-controlled dc motor operates at steady state, with an armature drive voltage va = 10 V. The motor runs at 600 rpm, and the armature current is found to be ia = 0.2 A. The armature resistance is Ra = 15 Ω. Determine: (a) The torque constant km of the motor (b) Electrical damping constant be (c) The efficiency under the given operating conditions, if the mechanical damping constant is bm = 8.25 × 10−5 N ⋅ m/rad/s (d)...
A series dc motor field coil has 4.5 turns and carries 225 A. The total armature reaction is 10.00 % of the field MMF. Calculate the net MMF produced.
The armature windings of a dc motor have a resistance of 8.0 Ω . The motor is connected to a 120-V line, and when the motor reaches full speed against its normal load, the back emf is 108 V. The load is increased so it causes the motor to run at half speed. What will be the current in the motor in this case? (Express your answer to two significant figures and include the appropriate units.)
A separately-excited DC traction motor of a metro train is in series connection, i.e., the armature and the field windings are connected in series with a common DC power source. The voltage of the DC power source is I (a) Please show that the angular velocity of the rotor is KT K where o is the is the angular velocity of the rotor, Ra is the resistance of the armature, Rris the resistance of the field windings, T is the...
An ac electric motor drives a dc electric voltage generator. If the motor operates a an efficiency of 90% and the generator at an efficiency of 80%, and if the input power to the motor is 5 kW, what is the output power of the generator?