electric machinery
chapter dc motor
qus=
200V DC series motor has Ra=0.5Ω and Rf=0.2Ω. the current input is 20 A, and the speed is 1000 r/min. if a resistor 0.2 Ω is joined in parallel with the filed winding, find the new speed of the motor for an input current of 20 A. Assume linear magnetization curve
electric machinery chapter dc motor qus= 200V DC series motor has Ra=0.5Ω and Rf=0.2Ω. the current...
A 8250 w shunt DC motor has a terminal voltage of 300 V. A field resistance Rf of 40 Ω, and an armature resistance Ra of 250 mm2. The field winding has 1500 turns. An adjustable resistance Rad is connected in series to the field winding. Rad is set at 20 Ω, but it can vary from 0 to 80 Ω. The magnetization curve is shown in Figure.1 and it is taken at a speed of 1200 rpm. (Armature reaction...
220 v dc shunt motor has Ra= 0.25 ohms and Rf=120 ohms . At no-load the motor draws a current It=6A. And runs at 1500 rpm. At full-load the motor draws 62 A. the armature reaction at full load reduces the flux by 10%. Determine the rotational losses , motor speed at full-load, the shaft torque and efficiency.
RedID: Name: Question 3. (18 Marks) A 10-hp, 130V, series dc motor, shown here, has an armature resistance of 0.1 Ω and a series field resistance of also 0.1. The number of turns of series coil N,-500. At the load 60 A, the speed is 850 r/min. Its magnetization curve is shown below. The core losses are 220 W and the mechanical losses are 230 W at this load. Assume that the mechanical losses vary as the cube of the...
T u resistance in a DC is decreased while the motor is driving a ii. A 100-hp, 250-V DC shunt motor with compensating winding has an am 0.04 12 and a variable shunt field resistance R; 92. The magn ompensating winding has an armature resistance of shunt field resistance R, 12. The magnetization curve of this motor is shown in Fig. 1. At no load, the field resistor has been a . At no load, the field resistor has been...
3) A saperately excited DC motor has the following parameters: Ra = 10 Ke = 0.4 V/rpm. Wb O = 0.2 Wb The motor speed is controlled by a full-wave bridge rectifier. The firing angle is set at 45, and the average speed is 1500 rpm. The applied AC voltage to the input of the bridge rectifier is 220Vrms - 50 Hz. a) (10p) Please draw the complete circuit. (converter + motor) b) (10p) Please find the armature current. c)...
3) A saperately excited DC motor has the following parameters: Ra = 10 Ke = 0.4 V/rpm. Wb 0 = 0.2 Wb The motor speed is controlled by a full-wave bridge rectifier. The firing angle is set at 45°, and the average speed is 1500 rpm. The applied AC voltage to the input of the bridge rectifier is 220Vrms - 50 Hz. a) (10p) Please draw the complete circuit. (converter + motor) b) (10p) Please find the armature current. c)...
Problem 3: DC machine A shunt DC motor rated at V,'. 300 V, with field resistance of Rf 600 0, armature 0.2 , resistance of R, 30.5 A (total current) when rated-load at n, consumes 916.8 rpm. Armature rotational loss (consisting of fan, friction and core loss (consisting of field resistance, armature a) Find Prot (rotational load), Pshaft and efficiency at rated load. - Assume that the rotational loss is constant and P,aft is now 50% in the case of...
5.2. (15 pt.) A shunt DC motor has the following characteristics Prated 30 hp, Vt = 240 V; nated 1200 rpm Ra-0.19 Ω; Rs 0.02 2; Rotational losses at full load 3550 W rated= 110 A NF 2700 tums per pole NSE 12 turns per pole Radj 100 to 400 Ω 320 Speed = 1200 r/min 240 き 200 180 3 160 140 120 100 0 0. 0.2 0.3 04 0.5 0.6 0.7 0.8 0.9 1.0 1. 2 13 1.4...
1. A 300 V compound motor has armature resistance 0.18 Ω, series field resistance 0.3 Ω and shunt field resistance 100 Ω. The rotational losses are 200 W. On full load the line current is 25 A and the motor runs at 1800 rpm. Determine: (i) the developed mechanical power (ii) the output power (iii) the output torque (iv) the efficiency at full load 2. A 120 V series motor has 0.2 Ω field resistance. On full load, the line...
DC series MOTOR... LAB I need help answering question 6 and 7. Results and Discussion: 1. Plot machine speed vs resistance 2. Plot machine speed vs current 3. Explain the above plots 4. Using DC Motor Theory, explain the current profile Totque (mV) 12 you obtained Plot the motor speed against the input voltage. Explain the results obtained. Using the graph, right, determine the torque at each current setting. Plot the motor speed (n) against the torque (T) of the...