This document discusses simulating a single phase PWM inverter using unipolar and bipolar PWM techniques. It explains that bipolar switching turns on opposite switches simultaneously, resulting in an output voltage determined by comparing a control signal to a triangular carrier wave. Unipolar switching instead compares the control signal and its inverse separately to the carrier wave to determine switching of each leg. The document includes simulation diagrams and scope outputs comparing the unipolar and bipolar PWM inverter outputs.

1. Simulation of single phase PWM inverter
AIM:- To implement a single phase pwm inverter with Unipolar and Bipolar pwm
techniques
THEORY:- In Bi-polar switching, the diagonally opposite switches are turned on or
turned off at the same time. The output of leg A is equal and opposite to the output of
leg B. The output voltage is determined by comparing the control signal , Vr and the
triangular signal, Vc.
In Unipolar Switching, the devices in one leg are turned on or off based on the
comparison of the modulation signal Vr with a high frequency triangular wave. The
devices in the other leg are turned on or off by the comparison of the modulation
signal -Vr with the same high frequency triangular wave.
BIPOLAR PWM
Simulation Diagram

2. OUTPUT in Scope
OUTPUT in Scope2 (Inverter output)

3. UNIPOLAR PWM
Simulation Diagram
OUTPUT in Scope

4. OUTPUT in Scope2 (INVERTER output)
RESULT
Single phase PWM inverter with Unipolar and Bipolar switching is implemented .