Analysis and Design of Power Electronic Circuits using Orcad

Professor Babak Fahimi, PhD

Director, Power Electronics and Controlled Motion Laboratory

University of Texas at Arlington

Getting started with PSpiceTo start with a PSpice project:1) Go to capture CIS Lite Edition 2) Go to “File” menu. Select “New Project” option. 3) Choose “analog or mixed A/D” option and specify the project name and

its location and click Ok

4) Once the step 3) is completed the following window appears. Choose “Create a blank project” option

5) Create the circuit by placing all its parts using “Part” option from “Part” menu. In this way a complete electrical circuit can be formed.

Points to remember

• When creating a new project , use Analog or Mixed A/D set-up option.

• Watch the file location / directory structure.

Design and simulation of power electronic circuits

Power Electronic Circuits can be classified as:

• DC-DC Converters

• AC-DC Converters (Rectifiers)

• DC-AC Converters (Inverters)

• AC-AC Converters

Now design and simulation of each of these circuits will be discussed.

AC-DC Converters (Rectifiers)

AC-DC converters ( Rectifiers) can be classified as:

• Half wave rectifier

• Full wave rectifier

These can further be classified depending upon the rectifying element being used . If using diode, are called uncontrolled rectifiers. Whereas if

using thyristor, are called controlled rectifiers.

Half Wave Uncontrolled Rectifier

a) For Resistive Load

1) Make the circuit in PSpice using steps mentioned earlier.

Components used are: VSin (voltage source) DIN4002 (diode) R (Resistance) GND_SIGNAL/CAPSYM.

2) Make the simulation profile using “New Simulation Profile” command

from “PSpice” menu.

3) Go to “Edit Simulation Profile” in “PSpice” menu, simulation settings window will open. Go to “Analysis” and set the simulation parameters as shown below.

4) Run the simulation by using command “RUN” from “PSpice” menu.

5) Get plots for IR1(resistance current), RMS value of IR1 and V1(input voltage) using “Add Trace” command from “Trace” menu

6) Plot the resistance current and then use “Fourier” command from “Trace” menu to get the frequency response of the resistance current.

Half Wave Uncontrolled Rectifier

b) For RL Load

1) Create another page under same schematic and make the circuit using same steps.

Components used are: VSin (voltage source) DIN4002 (diode) R (Resistance) L ( Inductor) GND_SIGNAL/CAPSYM

2) Now simulate the circuit using same steps and get plots for resistance current and input voltage.

Half Wave Uncontrolled Rectifier

c) For RC Load1) Create another page under same schematic and make the circuit using

same steps. Components used are: VSin (voltage source) DIN4002 (diode) R (Resistance) C ( Capacitor) GND_SIGNAL/CAPSYM

2) Now simulate the circuit using same steps and get plots for resistance current and capacitor voltage.

Half Wave Uncontrolled Rectifier

d) For RL load with freewheeling diode

1) Create another page under same schematic and make the circuit using same steps.

Components used are: VSin (voltage source) DIN4002 (diode) R (Resistance) L ( Inductor) GND_SIGNAL/CAPSYM

2) Now simulate the circuit using same steps and get plots for resistance current , RMS value of resistance current and input voltage.

Half Wave Controlled Rectifier

For type (1) connections1) Make the circuit using same steps. Components used are: VSin (voltage source) VPULSE (voltage source) 2N1595 (Thyristor) R (Resistance) GND_SIGNAL/CAPSYM

2) Now simulate the circuit and get plots for resistance current.

Half Wave Controlled Rectifier

For type (2) connections (a) with zero time delay in gate pulse

1) Make the circuit using same steps.

Components used are: VSin (voltage source) VPULSE (voltage source) 2N1595 (Thyristor) R (Resistance) GND_SIGNAL/CAPSYM

2) Now simulate the circuit and get plots for resistance current and input voltage.

Half Wave Controlled Rectifier

For type (2) connections (b) with 4.1667ms time delay in gate pulse

1) Make the circuit using same steps.

Components used are: VSin (voltage source) VPULSE (voltage source) 2N1595 (Thyristor) R (Resistance) GND_SIGNAL/CAPSYM

2) Now simulate the circuit and get plots for resistance current and input voltage.

Full Wave Uncontrolled Rectifier

Full wave uncontrolled rectifier can be :

• Single phase

• Three phase

Single Phase Full Wave Rectifier

1) Make the circuit as shown:

2) Simulate the circuit and get plots for all diode currents.

Three Phase Full Wave Rectifier

1) Make the circuit as shown:

2) Simulate the circuit and get plots for all diode currents.

Points to remember

• In order to simulate the circuit signal reference must be named 0 ( the number zero)