The following details are known about a 150 hp motor, 240 V, 500 rpm, dc shunt...

The following details are known about a 150 hp motor, 240 V, 500 rpm, dc shunt motor. Nominal full load current: 500 A Insulation class: H Weight: 3400 kg

Find

1.The total losses and efficiency at full load.

2.Calculate the approximate shunt filed exciting current if the shunt field causes 20% of the total losses.

3.Calculate the value of the armature resistance knowing that 50% of the total losses at full load are due to armature resistance.

4.With your calculated armature resistance, determine the counter-emf.

5.Determine the torque of the motor at full load.

6.The supply voltage is decreased to 200 V, approximate the speed at this supplied voltage.

Expert Solution

Manojponduru answered 1 year ago

A 100 hp, 220 V, 1200 rpm DC shunt motor with an armature resistance of 0.05...

A 100 hp, 220 V, 1200 rpm DC shunt motor with an armature resistance of 0.05 ? and a field resistance of 50 ?. The motor has compensating windings, so armature reactance can be ignored. Mechanical and core losses may be ignored also. The motor is driving a drilling machine, TL ? (1/n). The motor is driving a load with a line current of 120 A and an initial speed of 1200 rpm. Assume Linear Magnetization curve i. What is...

23 hp, dc shunt motor is running at 1000 rpm when the armature voltage is 600...

23 hp, dc shunt motor is running at 1000 rpm when the armature voltage is 600 V. The armature resistance of the motor is 0.8 ohm, and the field resistance is 900 ohm. The efficiency of the motor at full load is 92 %. a) Calculate the value of the resistance of the dynamic braking at full load. The armature current should be limited to 150% of the rated value. b) If the motor operated in regenerative braking at a...

A 240 V DC shunt motor draws 40 A while driving a constant torque load. The...

A 240 V DC shunt motor draws 40 A while driving a constant torque load. The armature resistance is Ra = 0.2 Ω, the field resistance is Rf = 240 Ω and machine constant is Ka = 120. The part of magnetization characteristic (field flux versus field current) related to the question is: If (A) : 0.70 0.80 0.86 0.90 1.00 1.10 1.20 1.30 1.40 ϕ (mWb) : 5.80 6.30 6.59 6.70 7.20 7.60 7.96 8.20 8.45 The constant rotational...

A DC shunt motor drives a centrifugal pump at a speed of 1000 rpm when the...

A DC shunt motor drives a centrifugal pump at a speed of 1000 rpm when the terminal voltage and line currents are 200 V and 50 A, respectively. Given the armature resistance, Ra = 0.1 ohm and field resistance, Rf =100 ohm. Design a circuit which the speed of the motor can be controlled by using the added resistance method to the armature circuit and the maximum starting current is 120 A. Next, if the added resistance in the designed...

Problem 5) A long shunt 600 V, 1200-rpm DC motor has a series field winding resistance...

Problem 5) A long shunt 600 V, 1200-rpm DC motor has a series field winding resistance of 0.05 Ω, a shunt field winding resistance of 200 Ω, and an armature resistance of 0.1 Ω. The machine is connected to 600 V DC source. The rotational loss is 3.2 kW. If the machine draws a 100 A from the supply, calculate a. Back EMF b. Determine the machine’s converted power (or developed power) and its efficiency. c. Determine the speed regulation...

A 230 V, 500 rpm, 100 A separately- excited dc motor has an armature resistance of...

A 230 V, 500 rpm, 100 A separately- excited dc motor has an armature resistance of 0.1 ohms. The motor is driving, under rated conditions, a load whose torque is constant and independent of speed. The speeds below the rated speed are obtained with armature voltage control (with full field) and the speeds above the rated speed are obtained by field control (with rated armature voltage). What motor terminal voltage is needed to run it at 400 rpm? By what...

A 120+m -V , 2400+n-rpm shunt DC motor has a armature resistance 0.4+0.1*m ohm and a...

A 120+m -V , 2400+n-rpm shunt DC motor has a armature resistance 0.4+0.1*m ohm and a shunt field resistance of 160+m Ohm . The motor operates at its rated speed with full load which takes 15+m Amp. A small of current of 2+.1*m A at no load due to rotational loses. Assume that rotational loss is proportional to the speed. Find Field current at no load Armature current at no load Rotational loss at no load Armature current at Full...

A 400 V dc shunt motor has a rated armature current of 76 A at a...

A 400 V dc shunt motor has a rated armature current of 76 A at a speed of 1000 rpm. The armature resistance of the motor is 0.4ohm, the field resistance is 100 ohm, and the rotational losses are 0.9 kW. The load of the motor is bidirectional. Calculate the following: (a) No-load speed of the motor. (b) Motor speed, where the armature current is 60 A during regenerative braking. (c) Developed torque during regenerative braking. (d) Back electromotive force,...

Assuming n=m=1 A 120+m -V , 2400+n-rpm shunt DC motor has a armature resistance 0.4+0.1*m ohm...

Assuming n=m=1 A 120+m -V , 2400+n-rpm shunt DC motor has a armature resistance 0.4+0.1*m ohm and a shunt field resistance of 160+m Ohm . The motor operates at its rated speed with full load which takes 15+m Amp. A small of current of 2+.1*m A at no load due to rotational loses. Assume that rotational loss is proportional to the speed. Find a. Field current at no load b. Armature current at no load c. Rotational loss at no...

A 230 V, 250 rpm, 100 A separately excited dc motor has an armature resistance of...

A 230 V, 250 rpm, 100 A separately excited dc motor has an armature resistance of 0.5 Ω. The motor is connected to 230 V dc supply and rated dc voltage is applied the field winding. It is driving a load whose torque-speed characteristic is given by TL = 500 − 10ω where ω is the speed in rad/sec and TL is the load torque in N-m. Find (a) the steady state speed at which the motor will drive the...

Question