Calculate the induction motor efficiency, Mechanical Engineering


Characterisation tests have been performed on a four pole, 415 V (line to line), three phase, star connected, 50Hz induction motor, with the following results:

  • No-load test : 415Vl-l, 3.76A, 234.3 W/phase.

(obtained at synchronous speed with a drive motor supplying the rotational losses of the drive system)

  • Locked rotor test: 163.8 Vl-l, 30A, 603 W/phase.

a)  Draw the per phase approximate equivalent circuit model of the induction motor, with all elements "stator-referred". Identify the physical significance of each element in the model.

b)  Using the characterisation data, calculate the "stator-referred" induction motor parameters. Assume that the shunt elements are much larger than the series terms. Remember that the measured input voltages are "line-to-line", not phase voltages.

c)  A load test is performed on the induction motor, which is fed from a 415Vl-l 50Hz supply, and the rotor speed is measured to be 1410rpm. Calculate the output mechanical power and mechanical torque for this test if the rotational losses constitute 880W for this condition. [Hint : Assume that the stator and rotor winding resistances are split equally].

d)  Calculate the induction motor efficiency for the load test described in (c).

e)  It is required to run the induction motor at a no-load zero slip speed of 900 rpm. Neglecting rotational losses, what must the supply voltage and frequency be in order to achieve this speed?

Posted Date: 2/18/2013 2:43:17 AM | Location : United States

Related Discussions:- Calculate the induction motor efficiency, Assignment Help, Ask Question on Calculate the induction motor efficiency, Get Answer, Expert's Help, Calculate the induction motor efficiency Discussions

Write discussion on Calculate the induction motor efficiency
Your posts are moderated
Related Questions

Q. Design Wellheads and Wellpads? Hydrocarbon-producing wellheads and wellpads shall be located in open, well ventilated areas with as much segregation from other critical equi

(a) Calculate the natural frequency of mass m = 1 Kg placed at one end of a cantilever beam of negligible mass. Length of cantilever = 500 mm, d = 30 mm, b = 20 mm, E = 210x10 9 N

what is the meant by kleins construction?

Location of centre of gravity of a hemisphere: Find out the location of centre of gravity of a hemisphere of radius a. Solution Figure shows the cross-section of the h

At a fixed point in a strained material the intensities of normal stress on the planes at right angles to each other are 20 N/mm 2 and 10 N/mm 2 . Evaluate the principal stresses

A piece of Al weighing 6 kg and initially at a temperature of 300 O C is suddenly immersed in a fluid at a temperature of 20 O C. The convectice heat transfer coefficient is 58 W/m

Define the Boundary Representation of solids Boundary model or b-rep model is based on the topological notion that a physical object is bounded by a set of faces. These faces a