Hi there, i have two questions that i am totally stuck on
1)
A pump is to be driven by a 415V, 4-pole, 3-phase 50Hz, star-connected, synchronous
motor. The pump has the following torque-speed relationship.
T= 0.5(N)^2
N is the pump speed in revs/s and T is pump torque in Nm. The synchronous
reactance of the motor is
1(ohm)
For a leading 0.7 power factor condition, calculate
i) Line current
ii) Field induced EMF
iii) Load angle
2)
A 4-pole, 1460 revs/min induction machine, connected to a 50Hz supply, has the
following Thevenin equivalent circuit elements;
VT = 227V,
RT =1.4(ohm),
XT = 2.5
and the rotor circuit elements are
R2 = 1.2,
X2 = 2.3.
Calculate (i) rotor current, (ii) rotor loss, (iii) mechanical output power and (iv) torque at
the rated speed of the machine.
1)
A pump is to be driven by a 415V, 4-pole, 3-phase 50Hz, star-connected, synchronous
motor. The pump has the following torque-speed relationship.
T= 0.5(N)^2
N is the pump speed in revs/s and T is pump torque in Nm. The synchronous
reactance of the motor is
1(ohm)
For a leading 0.7 power factor condition, calculate
i) Line current
ii) Field induced EMF
iii) Load angle
2)
A 4-pole, 1460 revs/min induction machine, connected to a 50Hz supply, has the
following Thevenin equivalent circuit elements;
VT = 227V,
RT =1.4(ohm),
XT = 2.5
and the rotor circuit elements are
R2 = 1.2,
X2 = 2.3.
Calculate (i) rotor current, (ii) rotor loss, (iii) mechanical output power and (iv) torque at
the rated speed of the machine.
