Machine and Power Electronics Lab

Lab Incharge: Raju Shrestha, raju.shrestha@pcampus.edu.np

Lab Technician: Krishna Saud

1. Electric Machine I- Lab

This lab is based on the subject “Electric Machines I” which is the core subject of Electrical taught to the second year.

  1. Magnetic Circuits
  • To draw a B-H curve for two different samples of Iron Core
  • Compare their relative permeabilities
  1. Two Winding Transformers
  • To perform turn ratio test
  • To perform open circuit (OC) and short circuit (SC) test to determine equivalent circuit parameter of a transformer and hence to determine the regulation and efficiency at full load
  • To examine exciting current harmonics
  1. DC Generator
  • To draw open circuit characteristic (OCC) of a DC shunt generator and to calculate: (a)Maximum voltage built up (a)Critical resistance and critical speed of the machine
  • To draw load characteristic of a shunt generator
  1. DC Motor
  • Speed control of DC Shunt motor by (a) armature control method (b) field control method
  • To observe the effect of increasing load on DC shunt motor’s speed, armature current, and field current.
  1. 3-phase Induction Machines
  • To draw torque-speed characteristics and to observe the effect of rotor resistance on torque-speed characteristics
  • To perform no load and blocked rotor test to evaluate equivalent circuit parameters

2. Electric Machine II-lab

This lab is based on the subject “Electric Machine II” which is the core subject of Electrical taught to third-year students.

  1. To study No-load characteristics of a 3-phase synchronous generator
  2. To study load characteristics of a synchronous generator with (a) resistive load (b) inductive load and (c) capacitive load
  3. To study the effect of excitation on the performance of a synchronous motor and to plot V- curve
  4. To study the effect of a capacitor on the starting and running of a single-phase induction motor
  5. To study the operating characteristics of universal motors

3. Power Electronics Lab

This lab is based on the subject “Power Electronics” of our fourth-year students. There is a total of 5 lab assignments. Following are carried out:

  1. Study of single-phase rectification with diode and thyristor
  2. Study of three-phase rectification with diode and thyristor
  3. Study of DC conversion using chopper circuit
  4. Study of DC to AC conversion with resistive load
  5. Study of AC voltage controller with resistive load

4. Utilization of Electrical Energy

This lab is based on the subject “Utilization of Electrical Energy” which is taught to fourth-year students. There are total of 4 lab assignments. This lab is carried out as follows:

  1. Speed Control of DC shunt motor by controlled rectifier
  2. Speed Control of Induction motor by rotor rheostat method
  3. Speed Control of Induction motor by the frequency control method
  4. Study of PWM controller for an ac machine